PAV/PDSD dsd issue

Hello, I am the original owner of a flawless PAV/PDSD combo that I still am in love with. Recently, the PDSD lost the ability to decode all PCM input signals - it will only decode Dolby Digital. I have tried getting into the factory settings and resetting the system, unplugging for a day and restarting, making all of the inputs inactive any only using one active input and still - get a “DSD ERROR 2” code. Desperate to get it fixed - incredible that it has functioned perfectly for so many years. Any suggestions? Any kind of help would be greatly appreciated; service manual, name of a service center that has a lot of experience w/ proceed, personal experience where your unit was fixed - thank you!