Hello again, Does PT 2011 handle higher bit settings, say 24/48 etc without any problems?

The reason I ask is I set my settings at 24/44.1 for a higher quality recording, match it with my soundcard's settings, set the buffer size at 512, but after recording several stereo audio tracks, pT crashes and I have to do a forced shutdown, losing my work. It's happened twice.

My computer is a Dell 15z XPS, I run Win 7 64-bit, 2.8-3.4 (turbo boost to 3.4) ghz core 2 duo chip, 8 GBs Ram, a 7200 and a 10,000 rpm external SATA drive, and use an Avid (M-Audio) Fast track C400 USB 2.0 sound interface. I've tried re -installing the C400's drivers, as well as reinstalling PT, but PT still crashes.

I record to drive E:, the SATA external drive, and have PT and OS and save project file to drive C:

Is PT more stable with say, 16 bit recording as opposed to 24 bit?

Anyone have any ideas? Thanks in advance for any help.