Causing the Alesis MultiMix 12 (or 8 or 16) Firewire Mixer to Function with Dell Latitude C640

It seems common that many have problems getting this Firewire mixer to function reliably. I was caught in this trap. The result for me was significant problems with the software DAW (usually cakewalk/Home Studio, though I also use Cubase, Reaper, Audacity, ...), and audio dropouts. 

My host machine is a Dell C640, 2 GHz P4, with 1GByte mem, internal 7200 RPM disk and external 7200 RPM disk. Not that great, but should be quite functional for this purpose. Since this fine unit does not have a native Firewire port, I'm using a Firewire adapter plugged into the PCM/CIA port. Of course it's so tall that I can't also insert a USB 2.0 adapter.

I tried different ASIO buffer settngs, read/write buffer settings, Windows XP (ugggghh) settings, and every hint I could find by googling. Nothing seemed to do the trick.

For other reasons, I installed a very nice fan control utility, i8kfangui, from http://diefer.de/indexe.html. This also shows the temperatures of the disks, some system components and, most interestingly, the CPU speed.

Since the CPU on this computer offers the SpeedStep option where the cpu speed is adjusted for better power management, I naively suspected disabling this in the BIOS would cause it to offer full speed performance. Not! Note the quote from master Diefer:

During the development of Windows XP, Microsoft decided to integrate dynamic frequency switching into the operating system itself.

Clearly this is not good, particularly since it's very obscure what power settings mean "run the CPU at full speed all the time".

I believe Intel offers a CPU speed control application, but tried SpeedswitchXP from http://diefer.de/speedswitchxp/index.html. It worked great. Since installing it and setting the CPU to full speed when on AC power I've been able to record many tracks concurrently while also monitoring on the Alesis mixer.

All ASIO buffer settings result in significant recording duration improvements. But just to be sure, I tried this test. For a number of different different buffer sizes (set in the Alesis Firewire ASIO control panel) I recorded 2 stereo and 2 mono tracks and waited for the audio engine to die. Here's the results.

Buffer Size

512

768

1024

1536

run 1

2 hrs 30

1 hr 28

6 hr 21

3 hr 55

run 2

4 hrs 24

1 hr 33

run 3

55 min

1 hr 48

This is significantly better than the, uh, few minutes before setting the CPU speed.

I've also been successful recording 6 tracks (2 stereo, and 2 mono) while monitoring. Much improved!