Recording drifts

I am using Audacity for about 2 years. Recently I have some problem with recording. I can start a record correctly at the right beat, then the recording start drifting. It drags and drags. For a piece of about 150 second long, the final beat will be off about 1 second. Is there any tips and suggestions I can use to correct this problem. I am using Windows XP with SP2.

Thanks in advance for any possible help.

You’ve got a clock drift problem. The first thing to do is try recording at a different sample rate. That might work, but the problem is usually a hardware problem (though I can’t prove that). Try some new hardware and see if the recording works right (but make sure you can return it if it doesn’t help, USB/FireWire devices can usually be returned).