Long time Slackware user (1996) and lurker (2001ish), first time poster...

I normally use Slackware64-current for my computers for that bleeding-edge thrill. I recently installed S64-current on my Dell 7920 (dual Xeon 4114s) with an Intel ARC A770 GPU hooked up via HDMI to a 4K Hisense A6H. It was installed April 3rd. The system was running perfect, so I upgraded it on May 10th to the latest S64-current. Unfortunately, that broke some stuff... normally, I am pretty good at fixing any problems. In fact, since the 6.6.30 kernel broke gaming, I immediately regressed to 6.6.29 to fix that.

However, the upgrade also seems to have broken the sound over HDMI. Basically, the sound is cutting out... I only get about 10%-40% of the sound coming out the TV I am using as a monitor. I regressed back to the 6.6.24 kernel* packages that were originally working. Looking at the other packages that were upgraded in S64-current between Apr 3rd and May 10th, nothing else seems sound related, except pipewire (1.0.4->1.0.6) and wireplumber (0.5.1->0.5.2), but I'm still using pulseaudio.

Sound going out the 7920's motherboard's sound card is fine. I also have a laptop (Thinkpad P71 with a NVidia GPU), also running S64-current (May 10th)... also displaying on the same Hisense A6H via HDMI... that sound is fine.

While trying to figure out the problem, I inadvertently booted my Dell 7920 into Window 10 Pro... and surprisingly, the sound is also dropping out there over HDMI as well.

I immediately thought it must be a hardware problem... so I swapped out the ports, the HDMI cable and triple checked my settings. It just seems so strange that I would suddenly have a hardware problem right as I reboot for my upgraded Slackware.

I AM STUMPED. Bear with me, since I acknowledge that this sounds like a hardware issue, but I am posting here because I'm curious if there was any package that got upgraded between Apr 3rd and May 10th that would affect the sound using the A770's HDMI for sound.

I am open to any other suggestions.

BK

Can't really help, this is just a rant so, moderators feel free to act accordingly: whomever invented and made HDMI "the standard" should be sent to a desert island.

Sounds silly but, did you try to unplug everything from the wall for at least 3 minutes? Monitor, computer, the receiver (if any) in-between? Maybe try another monitor or a tv until the imaginary settings (that your hdmi ports got an accidental handshake on) are flushed away.

Actually, yes, I did try that a few times.

I'm not so sure it feels like a HDMI handshake problem, but more like an IRQ problem. I thought perhaps something might have reshuffled resources after the software upgrade. Unfortunately, things sometimes configure themselves automagically today so I suspect software that might reconfigure hardware. Unfortunately, it's been years since I built my own kernels, so I'm a bit rusty on the modules and firmware of the kernel and the lower level daemons and such.

BK

I did figure out this problem. It was one of three very persnickety BIOS settings that I have not narrowed down yet... I suspect it has to do with the PCIE settings that make way for Thunderbolt 4... It seems to have interfered with my ASUS BT400 Bluetooth, as well.

Why the -current upgrade and reboot process triggered this, I don't know. Perhaps a VERY coincidental stray gamma ray tweaked my BIOS.

I will say this... I don't love the Dell 7920 BIOS. UI really needs a mouse, but the mouse movement is jerky, some items are hard to find, others are phrased badly... and at least one setting just doesn't stick between reboots (I suppose I should submit a bug report), but doesn't seem to make much of a difference. And, of course, it doesn't allow me to get resizable BAR, even though the mundane options seem to go on and on.

Anyway, I'll probably break everything again later today when I once again upgrade to the edge of the -current blade. We'll see.

BK

I'm quite curious. Are you strictly Pulseaudio or have Pipewire enabled? It's easy to try both thankfully (enable/disable toggle scripts) but I will be overjoyed when Pulse finally is buried and forgotten and Pipewire, or something like it is the standard.

1 members found this post helpful.

Simple suggestion, Try another HDMI cable? I had more problems with HDMI cables being or going wonky than almost any other connector.

To be clear, I did figure out the main problem. A bad BIOS setting. I'm about to upgrade -current again, with the morbid curiosity to see if somehow my BIOS setting gets bonked again... then I will likely mark as solved.

I've read that here and there for some time. Historically, I haven't had an issue with Pulseaudio... but I did switch to Pipewire, as I was also having sound drop outs with my bluetooth headphones. I also upgraded my motherboard firmware and the firmware on my Arc A770... and regressed through Linux kernels back to 6.6.24.

Actually, I tried my other HDMI cable and bought a third one... swapped the HDMI ports on the TV... then tried a Displayport->HDMI adapter.

BK