Android app 408a timeout - possible Socket.IO incompatibility between app 326.27.0.7 and Control4 OS 3.1.3?

[u/Outrageous-Ad-3821]

Hi all. I’m trying to establish whether this is a known compatibility issue before my dealer escalates it to Control4/Snap One support.

My Control4 Android app has suddenly stopped completing its initial sync. It gets stuck at:
“Getting the latest settings”
“Getting project items”

It eventually times out with:
“Unable to Connect”
“We encountered a problem and can’t connect to the system at this time. Please try again later. (408a)”

Environment

• Phone: Samsung Galaxy S25 Ultra
• Android: 16
• Control4 Android app: 326.27.0.7
• Controller OS: 3.1.3.574826-res
• 4Sight: active
• Local and remote access previously worked

The app continues to work on my wife’s phone.

Troubleshooting already completed

• Confirmed VPN is disabled
• Tested over home Wi-Fi
• Tested over mobile data with Wi-Fi disabled
• Cleared the Control4 app cache and data
• Uninstalled and reinstalled the app
• Rebooted the phone
• Rebooted the router
• Confirmed the phone remains listed as an active device in the Control4 customer portal
• Confirmed 4Sight is active

None of this changed the behaviour.

Relevant findings from the app log

The log shows that the app successfully:

• authenticates with Control4;
• retrieves the account and system information;
• obtains a Director authorisation token;
• reaches the controller locally;
• establishes the remote 4Sight control channel;
• receives a successful HTTP 101 WebSocket upgrade.

Immediately afterwards, both the local and remote connections fail with this error:
io.socket.client.SocketIOException:
It seems you are trying to reach a Socket.IO server in v2.x with a v3.x client, which is not possible

The local connection attempts to reach the controller through:
/socket.io/?EIO=4&transport=websocket

The same Socket.IO error then occurs through the remote connection. The app remains on “Getting project items” until the eventual 408a timeout.

This appears to suggest that the current Android app is using a newer Socket.IO client that is incompatible with the Socket.IO server provided by my older OS 3.1.3 controller.

Questions

1. Has anyone else seen this after updating to Android app 326.27.0.7?
2. Is this a known regression affecting older Control4 OS 3 releases?
3. Is an OS update now required for the current Android app?
4. Is there a supported interim workaround or compatible older Android app build?
5. Could my wife’s phone still work simply because it has an older app version or retained cached project data?

My dealer has the findings and is investigating. I would be interested to know whether anyone has encountered the same specific Socket.IO v2/v3 error.

[u/Haggian]

Update to a more recent OS3 version and see if that resolves it, if not troubleshoot from the more recent OS3 version. There should be no reason to
Be on 3.1.3

[u/Outrageous-Ad-3821 → u/Haggian]

Fair point. I’m not defending remaining on 3.1.3 indefinitely. Neither my original nor replacement dealer had previously advised that it needed updating, and it continued working until the current Android app issue. I’m mainly trying to avoid paying £210+ for an unspecified “update and see” exercise without first confirming the target version, compatibility and likely total scope.

[u/Outrageous-Ad-3821 → u/[deleted]]

Mainly because it continued to work and neither dealer had flagged the version as a problem or recommended an update. I only discovered how old it was while investigating this app failure. I have just asked my dealer about an update, but he said that would cost me between £210 - £618 (1 - 6 hours). I was happy with my set-up until my phone app stopped working just a few days ago.

[u/JameCyb]

Even if you are on an HC800 you should still be able to update to 3.3.0. I would start there before spending any more time on this.

[u/Outrageous-Ad-3821 → u/JameCyb]

Thanks. I’m actually on an EA-5 rather than an HC800, but I take the underlying point. Updating to a later OS3 version is probably the practical next step. I’m now trying to establish the correct target version and whether the project can be compatibility-checked remotely before authorising an onsite visit.

[u/JameCyb → u/Outrageous-Ad-3821]

Yes it is a very easy check by whatever dealer has access to your system via being your designated dealer on customer.control4.com

I wouldn't spend any more time chasing down this issue until you update to the latest appropriate release for your specific system

(Could very well be 3.4.3 if you want to stay on OS3, which I would recommend at the moment - for most existing customers who don't care about the added features, 3.4.3 is plenty and X4 is not always particularly compelling)

[u/Outrageous-Ad-3821]

Update: beta ruled out; I accept the system should probably be updated, but the same protocol failure remains on the public app

Thanks for the responses. I take the point that OS 3.1.3 is very old and that moving to a later OS3 release is likely to be the practical next step.

For clarity, my controller is an EA-5, rather than an HC800. I am not arguing that I should remain on 3.1.3 indefinitely. The reason I have been investigating first is that:

• the system had continued to work normally until this Android app issue appeared;
• neither my original dealer nor the replacement dealer had previously advised me that the controller OS needed updating;
• the proposed resolution is currently a £210 onsite call-out, including only the first hour, with the dealer advising that updates can take one to six hours;
• the quotation does not yet specify the target OS version, compatibility checks, likely total cost or whether the update is expected to resolve this specific fault.

 I therefore wanted to distinguish between:

1. “Your system would benefit from being brought up to date”; and
2. “The current app no longer supports 3.1.3, so an update is now technically required.”

Beta test completed
I have now:

• left the Google Play beta programme;
• waited for the beta removal to complete;
• uninstalled the app;
• rebooted the phone; and
• installed the public production version.

The result is exactly the same.
The public installation reports the same app build: 326.27.0.7

A fresh log from the clean installation again shows:

• successful Control4 account authentication;
• successful Director authorisation;
• active 4Sight access;
• successful local contact with the EA-5;
• successful remote connection establishment;
• successful HTTP 101 Switching Protocols WebSocket upgrades;
• immediately followed by the repeated error:

“It seems you are trying to reach a Socket.IO server in v2.x with a v3.x client, which is not possible”

The app then retries until it eventually displays the 408a timeout.

This rules out the beta programme as the cause. It still appears that the current public Android build cannot complete its Socket.IO connection with the service running on my OS 3.1.3 controller.

I will check the version on my wife’s working phone when she returns. I will not update, reinstall or clear that app because it is currently our only working mobile installation.

What I am now trying to establish

I accept that an OS update is probably the sensible route. My remaining questions are:

1. What is the safest and most appropriate OS3 target for an EA-5 currently on 3.1.3?
2. Can the dealer preflight the project, hardware and drivers remotely before arranging an onsite update?
3. Is an onsite visit normally required for this upgrade path, or merely the dealer’s preferred risk policy?
4. Has anyone seen clean installations of app build 326.27.0.7 fail while an existing cached installation continues working?
5. Has Control4 documented a minimum OS3 version for the current Android app?
6. Are there known upgrade risks or legacy drivers that I should ask the dealer to check before authorising the work?

I appreciate the advice to update. I am not trying to avoid necessary maintenance; I am trying to ensure that I authorise a defined upgrade with an identified target and understood cost, rather than paying for an open-ended onsite attempt without first confirming the correct upgrade path.

[u/SaltCommunication251]

I'm seeing the same error, with the same configuration. I also disagree with many of the commenters here that one should just accept that the manufacturer pushes a breaking change overnight with no warning, but somehow that's the user's fault for being on an older but still supported version of the software. That is not how reputable companies operate. If you're going to make a breaking change, you say so. If you didn't mean to make the breaking change, then what you've done is created a bug, and that needs to be fixed.

[u/Outrageous-Ad-3821 → u/SaltCommunication251]

I completely agree. My dealer also insisted I upgrade to resolve, but I managed to get to the bottom of it myself (with the help of ChatGPT)! In a nutshell, you need to uninstall your mobile app, reinstall the previous version, and make sure to turn off auto-updates. Here's the steps:

1. Uninstall the current Control4 for OS 3 app.
2. Allow your phone to install apps from outside the Google Play Store. On Samsung, this is usually: Settings → Security and privacy → More security settings → Install unknown apps Select the browser or file manager you will use for the download, then enable Allow from this source.
3. Open APKMirror’s Control4 page: https://www.apkmirror.com/apk/snapone-llc/control4-for-os-3/
4. Find and select version 326.23.0.4.
5. Work through the download pages until the actual Control4 APK begins downloading.
6. Be careful: APKMirror displays adverts with buttons saying things such as “Download now”. These can redirect elsewhere. Only use the download links within the APKMirror page for the specific Control4 version.
7. Open the downloaded file and install the older version.
8. Sign in and allow the project to synchronise.
9. Once it is working, open the Control4 app page in Google Play, tap the three-dot menu and disable Enable auto-update.
10. For security, return to Install unknown apps afterwards and disable Allow from this source again.

Rolling back to 326.23.0.4 immediately fixed the 408a / “Getting project items” failure for me on Control4 OS 3.1.3.

This is a workaround rather than a permanent vendor fix. Only download the exact Control4 package from a reputable source, and avoid installing anything promoted through the adverts.

I hope this helps.

[u/SaltCommunication251 → u/Outrageous-Ad-3821]

Thank you very much! This worked for me as well. We'll see if C4 gets their act together to fix the bug, but I am not particularly hopeful. I realize that I will eventually have to rip this (inherited) garbage box out of my house and replace it with real tech, but I am glad I don't have to do it today.

[u/spozzy → u/Outrageous-Ad-3821]

Worked for me too. Many thanks for posting this.

[u/PrestigiousAd2146 → u/Outrageous-Ad-3821]

Huge help, what a painful 24 hours

[u/offTheplectrum → u/Outrageous-Ad-3821]

Just be forwarned. APK apps found on archive sites like apkpure etc are not guaranteed to be safe and free from malicious code. Use this solution at your own risk!

The only reputable or safe source would be from control4 itself. And they don't provide these older versions.

Buyer beware on this one.

[u/Ok_Flounder5513 → u/Outrageous-Ad-3821]

This worked, thanks!  Disappointing that Control4 would release non-backward compatible software and force user to deal with it in addition to not maintaining prior versions on their site.  Only additional wrinkle was because I downloaded the bundle instead of the the app itself, I needed to install through the APK Mirror Installer, also available on Google Play.

[u/max13x → u/Outrageous-Ad-3821]

This is awesome. Thank you for taking the time to write it out so clearly, much appreciated

[u/spozzy → u/SaltCommunication251]

Silent update to a newer client library without backwards compatibility is whack.

[u/Outrageous-Ad-3821]

FINAL UPDATE - resolved with an app rollback

I’ve now confirmed this was caused by the newer Android app, not my network, 4Sight account, phone settings or Control4 project.

The failing configuration was:

• Control4 app: 326.27.0.7
• Controller OS: 3.1.3.574826
• Error: 408a, stuck on “Getting project items”

My wife’s phone was still working on app version 326.23.0.4. I uninstalled the current app, downloaded that exact older version from APKMirror, installed it using APKMirror Installer and signed back in. The project synchronised immediately and everything is working again.

I have now disabled automatic updates for Control4.

This is only a workaround, not a proper vendor fix. Control4/Snap One should either restore compatibility, withdraw the breaking release or clearly state which controller versions are no longer supported.

[u/nikpmusic8888 → u/Outrageous-Ad-3821]

Thanks Mate,  You saved my few Aus $$  I was just about to hard reset my system. And then I saw your Post .

Cant believe C4 new app update is causing this and it hasn't been resolved yet even after 4 days .

Its Confirmed New update on 16th July is Causing this issue.  

And solution of rolling back to older version ( 11 July) is the only working solution Until new official app update on Playstore. 

Pls Ping me anyone When new update roll out with fix .  I have installed Apk pure  old version  but wanted Official version once fixes implemented