Error while recording on Vista / HD spike

I know it is not the optimal software or OS but that’s what my drummer friend decided to use as it was the only PC that he could find that would run it.

He’s on latest version of Vista, 4 gig RAM, PC is fairly recent (1 year old), audio interface(s) are Presonus Firestudio Project (2 interfaces) on the latest drivers.

We cleaned up a lot of the junk in Vista - prefetch, eye candy and other crap processes like SQL server service(wtf is this even running?) and had a stable setup so far until the last few sessions.

He is on the latest version/patch of Cubase LE4.

We managed to track almost a whole album on the thing without a glitch until recently.

I took out the files to add my bass parts (I have exact same Cubase LE 1.4.3 whatever latest is, same as his) and returned them to his PC. We had to only change the audio card assignments (mine is Presonus FP10).

Ever since we started playing back and overdubbing on these we’ve been having bunch of Cubase errors. I can’t say anythign specifically as it seems to be sporadic and it just gives me “Cubase error, need to restart” message, then I have to save up the track as a new version because of the error.

Track count is about 32 tracks per song, give or take a few.
I had the vst performance gauge in LE4 open on the last tracking session and CPU and HD resources were almost at nothing - 2 to 5% maybe. The audio card latency was set on highest (4096). Presonus also have a setting in the driver where you can specify different priority levels for the audio card - danced around from normal all the way up to safe3, no difference, still same glitches.

Every once in a while we get a spike in HD that will clip the VST resources meter.

The HD that we record to is external USB drive. Has about 30% of space left on it.

Any ideas?

Idea 1 - don’t record to the external USB drive.

It’d be on the list of things to try. We were hoping to gain some extra performance speed from the fact that OS and software doesn’t run on the same HD that does the tracks.