Playback glitches in T2

[hammondc]

I am having some glitches during playback. It gets much much worse as I crank up the sample rate. The latency that is displayed in Tracktion is the only one that I can select, so there is no way to change it from 46 ms for 48Khz. The tracks are all 24 bit and on a seperate disk from the OS. The disk is a pretty good 8.5 ms seek time IDE drive. As I play the tracks, it gradually gets worse, so I assume some buffer is overflowing somewhere. Also, the PC is a 2.8Ghz P4 with 512 MB ram. CPU and physical memory do not seem to be heavily loaded in the task manager. I am running XP.

I have tried it through my Aardvark card and through the regular PC soundcard, but results are similar.

Any suggested config changes that I can try?

[IIRs]

46 ms sounds pretty high. First thing to check is that you have the Aadvark's ASIO drivers selected in the settings page..?

[valley]

on many ASIO cards you cannot adjust the settings from applications such as Tracktion. If there are no config options available, click the "asio control panel" button to bring up the ASIO driver interface for your card.

For an ASIO card, 46ms is ridiculous. You should be able to work at settings around 10ms very confortably.

[hammondc]

I definitely have the correct driver selected. I have done a bunch of fiddling with the Aardvark Manager (the ASIO control interface). When I drop the ASIO buffer size down, then the latency number changes. It goes as low as 8ms, but then I really get the glitches on playback, much much worse. Also, if I set to 96 Khz in Tracktion, I get alot more glitches. Is there a way to check to see if I am IO bound somehow on the disk drive? I have two drives connected in a master slave config. Is there some utility that I can run to tell me if I am getting sufficient IO?

[hammondc]

Ahhh, another clue to the mystery. I found something called Performance which is part of XP Admin Tools. I launch it and watch the disk cue, cpu, and paging rate. When the crap hits the fan, the paging rate is 100%, but the disk cue is less than 50%, so I am assuming my problem is memory related? The odd thing is that it does not look like all physical memory is being used in task manager. I tried changing the page file size, creating multiple page files, and setting the initial to the final size. Still the glitches in playback. One odd thing, when I changed the page file size, it still says that the actual file size is 736MB, even though the limits on the page file size are 1536MB. Odd....

[titanium]

0. Uncheck "enable real time priority mode"

1. Turn off all unnecessary services. Start|Run services.msc.
Here's the bare minimum required for music and network
Cryptographic Services
DHCP Client
Event Log
Network Connections
Plug and Play
Remote Procedure Call (RPC)
Windows Audio
Windows Management Instrumentation
Workstation

2. Set PCI latency to minimum on everything except your audio.
http://downloads.guru3d.com/download.php?det=951

3. Turn off any crapware set to autorun at startup.
Start|Run MSconfig.

4. upgrade to 1G RAM and disable paging

[hammondc]

Thanks for the suggestions. I did most of them. Didn't do the memory upgrade yet. The problem turned out to be the hard drive. After moving all of my files over to the primary and disconnecting the secondary drive, things work, glitch free. I found a utility that checks disk read rates. It turned out that something in my config makes the second drive go very slowly. Probably because I have them both on the same cable. I'll be buying another controller or going to firewire. Anybody have any experience using a firewire drive as the IO device for recording?