Distorted audio when recording to Audition

I'm having a problem with my audio that is doing my head in and it's only started since I've been using a new computer.

When recording audio into Audition using ASIO4ALL v2 so that I can use four microphone inputs, for about 1 in every 10 minutes the audio coming into Audition is distorted. Listening through my interface and there's no distortion at all.

I've tried all the different buffer sizes and sample rates but don't know what else to try.

And I can't find another drive that allows me to use more than two inputs to record at once, which I need.

Please help!