Audio via NVIDIA HDMI skipping

Question

Everything else regarding audio, HDMI (video) ja the video card works, except seemingly not randomly the audio skips if I direct it over HDMI to my TV. And by seemingly not randomly it is very reproducible, though I cannot tell what exactly triggers it.

Things that trigger a skip are definitely things like Variety changing the desktop wallpaper. This happens just about every time, causing 1-2 skips (each skip is under a second). Lots of typing (like I am doing now, causes skips every sentence or so). Lots of web page scrolling seems to trigger quite a bit of skipping too.

I thought at first it was disk activity, but it is not - for example opening a 200mb bz2 file doesn't cause a skip at all. Also, not doing anything, causes no skips, if I turn off Variety and don't do anything, I get perfect no skipping audio (streaming video or watching an AVI for example).

If the computer is busy, like after boot, the audio is very crackly at first, skipping more than playing. Once things settle down, skipping becomes only intermittent.

The computer is not out of resources and skipping happens even with a few programs open.

An insanely annoying problem which I've tried many ways to tackle, including;

• newer kernel
• newer HDMI drivers (via xedgers)
• various audio debugging tips from community help

When I use HDMI audio, I usually have a dual monitor setup. The audio is directed to HDMI, but mostly I use a monitor. I have however tried using only the HDMI TV as a monitor - skipping still happens without a dual monitor setup. When using attached speakers via the built in sound card, there are no problems.

My Alsa information output is here: http://pastebin.com/0jPHeYFt

Other stats:

• alsa-base 1.0.25+dfsg-0ubuntu4
• nvidia-304 304.125-0ubuntu0.1 (tried xedgers 340 I think with no better perf)
• pulseaudio 1:4.0-0ubuntu22
• Ubuntu 14.10 3.18.9-031809-generic

Motherboard is an Asus Z97-AR, BIOS American Megatrends Inc. 1304. NVIDIA card is GeForce GTX 760

       *-display
            description: VGA compatible controller
            product: GK104 [GeForce GTX 760]
            vendor: NVIDIA Corporation
            physical id: 0
            bus info: pci@0000:01:00.0
            version: a1
            width: 64 bits
            clock: 33MHz
            capabilities: pm msi pciexpress vga_controller bus_master cap_list rom
            configuration: driver=nvidia latency=0
            resources: irq:16 memory:de000000-deffffff memory:d0000000-d7ffffff memory:d8000000-d9ffffff ioport:e000(size=128) memory:df000000-df07ffff
       *-multimedia
            description: Audio device
            product: GK104 HDMI Audio Controller
            vendor: NVIDIA Corporation
            physical id: 0.1
            bus info: pci@0000:01:00.1
            version: a1
            width: 32 bits
            clock: 33MHz
            capabilities: pm msi pciexpress bus_master cap_list
            configuration: driver=snd_hda_intel latency=0
            resources: irq:17 memory:df080000-df083fff

Any tips on what to try and how to debug this more?

---

Edit 26th Nov '15. I've upgraded my BIOS to the newest version, which seemed to help a lot. There is still some skipping however, but at least this suggests problems with the Asus motherboard. On some forum thread I found a similarly sounding problem relating to pci related stuff, which got me to upgrade the BIOS version. I'll see next what the NVIDIA latest driver does, though it is only a minor upgrade from 352. I'll also try the /etc/pulse/default.pa edit as suggested in comments.

Answer 1

Open a terminal (CTRL+ALT+T)

Edit the pulse audio default files:

sudo nano /etc/pulse/default.pa

Replace load-module module-udev-detect to load-module module-udev-detect tsched=0, save file and reboot.

Good luck.

Answer 2

You are having very 'outdated' video drivers installed on your computer.
NVIDIA improved their drivers a lot since the release of 304 GPU drivers.
You should use the latest official drivers that support GEFORCE GTX760.

Uninstall every NVIDIA software by executing:

sudo apt-get purge nvidia*
sudo apt-get install ppa-purge
sudo ppa-purge ppa:xorg-edgers/ppa
sudo reboot

Now reinstall the NVIDIA drivers by executing:

sudo add-apt-repository ppa:graphics-drivers/ppa
sudo apt-get update
sudo apt-get install nvidia-358
sudo reboot