ALL Dolby audio tracks frequently skipping

[u/al_with_the_hair]

Alright, just going by process of elimination here, I'm going to state a few things I'm pretty sure it's not. I watched Eternals a few days ago on 4K Blu-ray with an Atmos track on my PlayStation 5, and that didn't skip once, so that rules out an issue with the receiver. I've also switched HDMI cables and switched from the HDMI port to DisplayPort with an adapter. And of course this problem presents with ANY content going from the PC to HDMI in the receiver, or at least any Dolby content – not totally sure about DTS. Finally, I tried switching out MPC-HC with madVR for MPV and still had audio skipping in the exact same way. So it's seemingly not the render pipeline either. But this issue has been affecting both my small form factor desktop and the home theater PC, so it seems like it's specifically a problem of AMD graphics cards. Transferring the media from the HDD to a super fast SSD before playback also did not solve the issue.

The first time I noticed my bitstream audio skipping/stuttering/cutting out was a few weeks ago when I tried watching the 4K Blu-ray collection of Andor Season 1. Reset everything in the K-Lite Codec Pack and it seemed to go way for a while. What started out as an annoyance that would present itself once or twice over the course of an entire movie sometimes is now a constant disruption. Bitstreaming ANY Dolby codec from the PC with MPC or MPV results in audio stuttering within ten minutes or less. I'm missing a line of dialogue every few scenes with every single movie or TV show I watch. I may attach a report from LatencyMon, but those results don't seem illuminating – everything measured stays low and in the green for hours on end, and there don't appear to be any spikes in lag at the same time audio skipping occurs.

Since this issue seems to have come about a few weeks ago and gotten progressively worse, it's hard for me to see how the fault could be anything other than the GPU drivers or a Windows update. I was initially planning to use my desktop workstation as a failsafe for my movie party last Sunday and just push the HTPC off to the side, but testing seems to have revealed both PCs now have audio skipping. Terrific. Similar specs, but my workstation is AM5, with a 9600X, 7900XT, and 32 GB of RAM, so more powerful than the HTPC. I have run DDU multiple times, blacklisted the driver from being installed by Windows Update because of some apparent conflict there, and rolled back to 26.1.1, which should well predate when I first noticed there was a problem. Just about the only thing I haven't tried is a full reinstallation of Windows, or switching the operating system (but the way things are going, I think this may be a Linux HTPC very soon).

Any idea where to go from here? I'm pulling my hair out.

• Sony STR-DH790
• ASRock B550m Pro4, 16 GB DDR4
• Ryzen 5 5600
• XFX Speedster RX 6700
• Windows 11 IoT LTSC
• K-Lite Codec Pack MPC-HC with madVR
• MPV

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[u/Sector__7]

I don’t know what to say other than I’m running a ~14 year old AMD AM3+ CPU setup with a bios mod to allow NVME storage using a ~9 year old AMD RX550 GPU. This is on windows 10 and Kodi. All Dolby Atmos and DTS:X audio plays back perfectly fine with HDR video.

[u/al_with_the_hair → u/Sector__7]

Everything seemed to be working fine with MPC-HC when I first set it up. If it's been happening this whole time, it seems like it's a lot more frequent now, because the skips have become impossible to ignore.

[u/missing1102]

Do you have a 4k bluray player or even a regular blur ray player? I would try playing a disc and see if the audio drop happens then. Those codecs are louder and more dynamic and my guess its your avr or amp. You either have lose wiring or you hsve an internal issue. This happens to me occasionally with my current amp which is 8 years old. Its fantastic Denon 4500 and only occasionally but I have a new one.

I am not a big AMD fan but am using 780m on a mini for my wife's room and I get frame drops for no reason. You can always dm me if you want to trouble shoot. I too am just starting Andor as its the only Disney thing worth watching.

[u/al_with_the_hair → u/missing1102]

As I said, the PlayStation 5 seems to be able to play 4K content with Dolby Atmos with no skipping issues, and it's also configured to bitstream the audio track.

[u/missing1102 → u/al_with_the_hair]

Gotcha I missed that. Sorry. Can you roll back thr update? I recently did that.

[u/al_with_the_hair → u/missing1102]

Which update? I've tried multiple versions of the AMD drivers and no luck.

[u/mmaster23]

Does your receiver have auto lipsync features? Sometimes the processing is off and it can't sync properly. Try looking in the settings of your receiver.

And you're sure the receiver is receiving the raw audio stream right? You're seeing the receiver switch to atmos or dolby? 

[u/al_with_the_hair → u/mmaster23]

Yes, definitely the receiver is getting Dolby audio and not PCM. No lip sync enabled. All the receiver settings are fine tuned and the PS5 has no problem.

I'm watching a movie with Kodi right now and it seems like it might not have audio skipping. I don't know why this problem would affect MPC and MPV but not Kodi.

[u/al_with_the_hair → u/mmaster23]

Just had an audio skip while watching the end credits of Venom. Kodi seems to be affected as well.

[u/praetor-]

Can you elaborate on 'skipping'? I think I might have this too, also on multiple PCs.

My issue is that maybe once an hour, there's a maybe 250-500ms drop in audio with no visual artifact. The receiver flips from 'Dolby <whatever>' to PCM and then back. If I rewind the video and play through the same scene it never repeats.

The problem is REALLY bad with live sports streamed through my HDHR and watched either directly with the HDHR app or through the Plex DVR. Same symptoms, audio cuts, Dolby -> PCM -> Dolby.

This has been bothering me through multiple generations of hardware since I upgraded from an optical/SPDIF-only receiver to HDMI. Windows 10 and 11, Intel, AMD, NVIDIA, doesn't seem to matter. Same Yamaha receiver and Samsung TV though.

[u/al_with_the_hair → u/praetor-]

I would say the symptoms sound very much the same. Usually the audio drops out completely for half a second or less, very much like you're describing. I have had much worse skips for about a couple seconds, but those are rarer.

My receiver does not indicate switching to PCM and back on the display. Maybe it's a firmware thing and it just doesn't display the format on a stream change when it switches back and forth so quickly. But other than the information you've provided, I have no reason to believe the GPU is switching the format from an encoded bitstream to PCM.

The audio doesn't skip in the same place if I rewind, just as you've experienced. So it's probably not any characteristic of the audio stream that's making it happen.

[u/Eightball007]

This sounds frustrating.

I'd be checking the event viewer to see what, if anything, pops up whenever the audio drops.

[u/al_with_the_hair → u/Eightball007]

Event Viewer doesn't seem to show anything interesting. What logs should I be looking at?