Audio latency in games using pulseaudio

[Elite_07]

I'm getting around 100ms audio latency when playing games. It's pretty annoying especially when playing fps games like Left4Dead 2 because of the noticeable difference between shooting and hearing the sound. I'm just wondering if anyone else had this problem, and if there are any fixes without losing the functionality of pulseaudio.

I'm using Ubuntu 13.04.

[Federal-Foe]

Pulseaudio seems to have a ton of compatibility bugs, I can't use Skype without my pulseaudio screwing up and playing flash/html5 content at 1.5 times normal speed. I've searched google for fixes, but couldn't find a working fix (it was one from 2009) in the abundance of other audiobugs caused by pulseaudio.

The people working on it really need to catch up with the latest developments. Either that or you could try using another audiodriver (maybe those devs care enough to fix something).

[Dusk of Oolacile]

Open the console and change the audio mix ahead value to half of what it is. It did work in another source engine beta (VTMB). Maybe it'll help, maybe the value doesn't even exist anymore. It's worth a try though.

[Hardtimes]

Any tweaks will be heavily dependent on your audio hardware. Try each of the following:

Open /et/c/pulse/daemon.conf in a text editor. Look for:

 resample-method = speex-float-3 

and change it to

 resample-method = speex-float-1 

There are a number of other resampling methods to choose from, requiring different cpu loads based on quality. Run

 pulseaudio --dump-resample-methods 

for a list

Next, after testing the above, try changing:

 default-fragment-size-msec = 10 

to

 default-fragment-size-msec = 5 

There's also /etc/pulse/default.pa. Find the line:

 load-module module-udev-detect use_ucm=0 

and change it to

 load-module module-udev-detect use_ucm=0 tsched=0

Test with each, one change at a time, reverting if there's no change. Back up both files before any edits.

[Elite_07]

Thanks for all the suggestions guys. I'll try some of these out and report back to you.

[Elite_07]

Ok, the only setting that really seemed to reduce the latency was "default-fragment-size-msec =". I set it all the way down to one and it reduced the latency to a more acceptable range, but it's still within the realm of it being noticeable. My resample-method was already set to speex-float-1 by default, and it seemed to be the fastest of all the resample methods.

I'm not sure what else I can do. This is literally the last problem I have with linux right now.

[Hardtimes]

Is this an onboard audio chip or a discrete card?

[Elite_07]

Onboard audio chip on the ASUS P8Z77-V LK motherboard. It says the the audio chipset is Realtek ALC892.