I am totally new to all this and not especially techie (though willing to learn...slowly) so please be gentle with me - I'd be very grateful for some help.

I have just started making some experiemental recordings with a DAW (I've tried a few and always get this issue), a usb Samson mic and occasionally a m-audio midi keyboard which also has a usb connection. I am just plugging the mic and the keyboard directly into my laptop and starting to play. I also use loops that are packaged with the DAW.

I've noticed that generally things sound fine for a few minutes, but then the sound starts to break down, with lots of 'crunchy' white noise interference. Also when I try to use the keyboard, as well as the sound breaking down it quickly becomes unresponsive.

I would be really grateful for any thoughts about what the most likely cause of this problem might be, and anything I can do to solve it. I wondered whether an external sound card might be a solution, just because this seems to be an obvious thing I am lacking. I'm doing this on the cheap and am defintely not expecting professional results, but would really appreciate any thoughts on changes I could make to get around this problem.

Thanks!