Unable to play m4a since upgrade to 6.5.2

[gideond]

Since upgrading to UMS 6.5.2 I can no longer seem to play back m4a files. MP3 still works fine. m4a does not seem to even be reading the tags correctly as the menu in my Yamaha smartphone app is showing the actual file names for these types of files instead of just the track number and name like all MP3 files do. This receiver supports m4a natively and it's never had to even transcode these before. Will be testing again tomorrow on another computer that is also running the same version of the software.

Edit: The problem is occurring on my Windows 10 Pro rig. My older Window 7 Home rig seems to be working fine. I tried reinstalling 6.5.2 on the Windows 10 computer to no avail. Clean install also did not work.

Update: This morning I powered up my Windows 7 rig again and immediately had the exact same issue the windows 10 rig is having. Nothing at all has changed since last night on this computer. Not sure what the issue is. Will try a clean install on this one later today and failing that I'll roll back to a previous build.

Update 2: Hopefully this is resolved. I used Revo Uninstaller on both computers to completely remove UMS. Revo found quite a few files that were being left behind in Program Files on both computers and a stray registry entry on the Windows 10 machine. Once it was completely gone, I installed 6.5.2 again and reconfigured to identical setting that I had before. At this point, both computers are streaming m4a correctly again. Evidently the installer was corrupting something on upgrade. I stopped by my place of business today and tried the upgrade on two computers there. One was done through the automatic update and the other via the offline installer. Both had the exact same issue with m4a playback. Don't know how widespread this is, but it's happened on every Windows computer I've run the update on so far.

[gideond]

Looks like this issue was not solved after all. It has since recurred multiple times. I never had any issues before this version of UMS. Also it seems to be certain files, not all m4a files that are effected. Nothing is making any changes to the files that I can detect. They have the exact same date stamp as before. I did discover that without closing UMS, I can open the same files in Foobar and run the Optimize m4a Layout function on them and then UMS will see them and play them fine. No other media player or media server is having any issues with the files. Not sure what exactly is happening here.

[gideond]

Some new info. This is apparently not an issue with all M4A files. It's only a select set of them. And it does not appear to be the files themselves that are the issues. It's a problem with UMS and caching. If I reset the cache in UMS the problem immediately resolves itself and the files play again. The next time I start UMS it's right back to not working again. This seems to be happening on two specific albums I play frequently. I've stripped all data from the files, optimized them, and retagged them and the problem still persists with these files. I may have to try ripping them again this weekend from the original source and see how they behave. I can't see a reason these specific files would be causing a caching issue though.

[Sami32]

Hi

Thank you for submitting your issue. What you have found is a regression in 6.5.2. I'm sorry to say so, but until the next version fix, all you can do is to downgrade to 6.5.1.

Thanks to @Nadahar for the fix