AC3 Import Media Not Working

I have 3 Resolve stations active. I often import raw AC3 5.1 (.ac3) files into media and timeline. This has always worked for years. AFAIK it's quit working with the most recent Windows 10 update I did; loss of function was NOT related to upgrading Resolve and I have 17.1.1 on all PCs. To test, I imported AC3 just fine in Resolve on the other two PCs. I reset my PC using a drive image from February and ability to import AC3 is returned. I just wish my problem resolution didn't have to be as drastic as wiping my PC and setting back 2 months into the past.

Again, I believe the loss of AC3 ability in Resolve *seemed* to be associated with a Windows 10 update but I can't be sure. Wondering if anyone else is having a problem or experienced this before and if so what is the workaround.

There's another thread about AC3 issues. I couldn't play the test file myself, but other Windows users could, so...the update theory may be valid.

I have the same problem. I tried switching back to an old version of DaVinci without success. For me it looks also like a Win10 problem. But only DaVinci has the problem with ac3 5.1.
Log file of DaVinci says "Unable to set audio output params for codec ac-3". I have no idea how to solve it.