Win11 - Audio repeatedly disappearing with simultaneous slowdown in Video playback (reduces to approx 75% of normal speed)

Hi folks, compliments of the season to you and hoping you maybe able to point me in the right direction here as I haven't been able to remedy the following issue that has become apparent since the Dec install of the K-Lite software. I've had a look through the FAQ + current forum topics also but please forgive me if I've missed a duplicate and am repeating known info.

CONFIG: The issue is with my HTPC being a NUC11 running Windows 11 and connecting VIA HDMI to a 7.1 Integra DRX receiver + Optoma UHD65 Projector
PROBLEM: I'm finding since the update that I'm repeatedly dropping audio (like no sound remains) when playing video content either via web streaming via Chrome, OR, more commonly when playing Movie files and/or TV Series episodes via WMPC in formats such as .MKV & AVI. The problem almost always appears when pausing and restarting content alongside switching between episodes etc. This means 5-10 times a session in frequency currently and the only way to remedy it until the next iteration is to either DISABLE then RE-ENABLE the AV Receiver as a Default Device under SOUND properties or alternatively RESTART the PC.

What's interesting about the issue is that when it happens, the audio disappears for everything on the PC including system sound = Spotify etc etc. What's perhaps more relevant, however, is that the video playback on whatever video source is playing (Chrome, WMPC) reduces in speed of playback to approx 75% and the moment I DISABLE and RE-ENABLE the Default Sound Device it immediately starts playing back at Normal speed again.

ANY ideas on what might be the culprit here? I appreciate any help moving forward to sort it out and a bog thanks in advance!

Cheers! KB

[
Codec Tweak Tool | Log file | Generated at 2023-12-26 17:13:14

##### System Information #####

OS: Windows 11 Enterprise (10.00.22631) (x64)
CPU name: 11th Gen Intel(R) Core(TM) i7-1165G7 @ 2.80GHz
CPU details: 2803 MHz | 8 core(s) | Family 6 Model 140 Stepping 1
Memory: 32384 MB
Screen size: 3840x2160 (32bits) (30Hz) (250%)
GPU: Intel(R) Iris(R) Xe Graphics
VendorID: 8086, DeviceID: 9a49, SubSys: 30048086
GPU memory: 1024 MB
GPU driver: igdumdim64.dll (Version 31.0.101.4575) (7-11-2023)
Audio device: USB Audio Device
Audio driver: USBAUDIO.sys (Version 10.0.22621.2506) (10-19-2023)

##### K-Lite Codec Pack #####

KLCP version: 18.0.0
KLCP type: full

Speaker conf: as is

MPC renderer: MPC VR (DX11)
MPC subs: ISR
MPC audio: Internal Audio Renderer
MPC decoder: h264=D3D11VA hevc=D3D11VA vp9=D3D11VA vc1=1 mpeg2=1

LAVFilters subdir found

##### Decoder Settings #####

LAV Video:
H264=DXVA2CB HEVC=DXVA2CB VP9=DXVA2CB VC1=0 MPEG2=1 MPEG4=1 WMV3=0

LAV Audio:
MP3=1 AC3=B DTS=B DTSHD=B EAC3=B TRUEHD=B AAC=1 Vorbis=1 LPCM=1 WMA=0

##### DirectShow Filters (32-bit) #####

(A total of 70 filters, 0 shown, 70 hidden)

##### DirectShow Filters (64-bit) #####

(A total of 70 filters, 0 shown, 70 hidden)

##### ICM Class Manager (32-bit) #####

(A total of 2 filters, 0 shown, 2 hidden)

##### ICM Class Manager (64-bit) #####

(A total of 2 filters, 0 shown, 2 hidden)

##### Default source filters (32-bit) #####

(A total of 56 default source filters, 0 shown, 56 hidden)

##### Default source filters (64-bit) #####

(A total of 56 default source filters, 0 shown, 56 hidden)

##### ACM and VFW Codecs (32-bit) #####

(A total of 14 codecs, 0 shown, 14 hidden)

##### ACM and VFW Codecs (64-bit) #####

(A total of 13 codecs, 0 shown, 13 hidden)

]

Chrome does not use any codecs from K-Lite. Neither does Spotify. Since the sound loss is system wide, codecs are certainly not involved as a cause. Problem is either in the sound driver or in the sound subsystem of Windows.

WMPC does not exist. Correct abbreviation is either MPC (our player) or WMP (windows player).

BIOS update for this problem:
https://www.intel.com/content/www/us/en/support/articles/000087953/intel-nuc.html

And older article with BIOS settings (probably obsolete with newer BIOS):
https://www.intel.com/content/www/us/en/support/articles/000060142/intel-nuc.html

https://community.intel.com/t5/Intel-NUCs/HD-audio-passthrough-on-NUC11PAHi5-not-working/td-p/1339091
Read this for instructions to update the BIOS twice to upgrade HDMI firmware.

Hi again and thanks for the replies. My apologies for the abbreviation mix-up also....you've probably figured out that I use the K-Lite version of MPC.

So comments taken on-bord regarding the codecs and where they play. I didn't associate them to Spotify for obvious reasons but didn't realise they didn't factor in the browser side. The issue happens when stop/starting or transitioning through content either using MPC or Web browser so must be broader as you point out....once it happens then there is no sound available anywhere (although the PC can't establish there's anything wrong using troubleshooting etc

Appreciate the Intel articles also - I'll check the settings mentioned in the older article but can confirm I'm running BIOS version 0052 with the more recent article referencing version 42 as the cause of the problems. I have got everything pretty well up to date (Windows/Graphics/BIOS etc) in my attempts to sort this out so the obvious stuff is sorted but the fault remains and tonight even my DISABLE & ENABLE of the Output device has stopped working so I'm completely without sound.

Thanks again for coming back to me and the suggestions - I'll keep looking.

You might want to apply the latest BIOS again just to ensure that the HDMI firmware is up-to-date. One of the Intel articles says that the firmware may not get updated during the first BIOS upgrade.

One other important thing to know is that when bitstreaming compressed audio the sound device runs in exclusive mode. That means that one application holds exclusive access to output audio. If you run other apps during that time that output sound, then those may be silent or take over access.

If you do not bitstream compressed audio, but instead decode on the computer, and output uncompressed audio, then you can run multiple sound apps at same time. In the audio device properties in Windows sound settings, you can even find an option to disallow exclusive access. Its on the advanced tab.

Chrome and Spotify are not bitstreaming. But you might be using it for video playback. So worth a test if this avoids the problem.

Also check what is running on background. Close all multimedia apps and whatever may occasionally uses sound notifications. Maybe one of those is causing the issue.