I am currently using Cakewalk Pro Audio 9, and I'm having trouble with my MIDI playback. I am using two soundcards, Echo Darla 24 and SB LIVE Value. Darla has no wavetable synth, so I am using the SB for MIDI. Anyway, whenever I play back MIDI tracks, I have an intermittent scratchy sound that is produced.
It seems to be worse when there are also audio tracks present in the project, but it happens without this too.

I should have plenty of PC power, as I'm using a Pentium III 450 and a pretty fast 13 GB hard drive with 128MB of RAM. I wouldn't think this would be the problem. Plus, it's not like I'm tring to play back 50 tracks or anything. It happens with even 3 or 4 tracks.

Also, I am having problems with the MIDI playback volume not being near loud enough. The output levels on the soundcard are set to max, so that's not it.

I am considering buying a sound module such as the NanoSynth from Alesis. Might this help?

Can someone shed some light on this for me?