828mk3 has stopped playback with windows audio but works with ASIO

[RickAlex]

I've had an 828mk3 for 14 years. It's worked well but a couple of days ago suddenly stopped playing windows audio. I can play and record fine using SoundForge and Motu ASIO drivers so the Firewire connection is fine, the interface is running and the audio connections are working. But if I try playing using a media player or YouTube for example it doesn't play. If I try playing back from Audacity with the driver MME I get an error "Error opening sound device, try changing the audio host, playback device and the project sample rate." Playback from Audacity also worked correctly prior to a couple of days ago. Note that I can play back correctly if I choose the PC mother board sound.

The 828mk3's Windows driver version is 2015-07-14 4.0.6.6814

The PC is running Windows 10 Pro.
16 GB RAM

Any suggestions would be gratefully received! Thank you.

[CharlzS]

Do you have something running in the background that's taken exclusive control of the Windows audio? If not, open the Device Manager and in the View menu select Show Hidden Devices. Expand the Sound, Video and Game Controllers category and the Audio Inputs and Outputs category. Any greyed out MOTU devices in either category? You can right-click and uninstall those, but don't use the checkbox to attempt to uninstall drivers. If you uninstall a greyed out device in S, V and G Controllers, it will remove associated devices in Audio I/O. Then restart.

[RickAlex]

Thanks Charles. No, I don't think there's anything which has taken control of the Windows audio. I also checked for greyed Motu devices in device manager. There aren't any. The Motu audio device shows up normally.

[RickAlex]

I've got the Windows audio working now. I restored Windows to a restore point before some updates were done 6 days ago and it started working again. The question is which update was the problem. Would be interesting to see if anyone else sees the same issue.

There were a couple of security updates done after the point which I restored to, a cumulative .NET update for .NET 3.5 and 4.8 and a cumulative update for Windows 10 version 21H1.

[CharlzS]

That's a strange one - ASIO worked, but Windows Audio didn't. IIRC from my 828 days, there's a option in the MOTU Audio config to switch to WASAPI or something along those lines. If you update again and the same happens, maybe try changing that option.