My guess is that there’s a miss-match in sample rates, and the sound card drivers are not correctly reporting it, so it is not getting automatically fixed.
Check the settings in the Windows Sound Control Panel and ensure that the sample rate there matches the sample rate in Audacity. Try both 44100 and 48000 Hz (the difference between 44100 and 48000 is about a half step).
It’s kind-of unusual for the sample rate to be wrong (digitally) unless you’ve got defective drivers. The driver communicates between the hardware & application to (hopefully) keep everything in agreement.
Are you playing back on the FastTrack, or on your regular soundcard?
If you are playing through the soundcard, try the FastTrack. …If the hardware clocks (oscillators) are off the sample rate will be off and that throws-off the speed & pitch. You won’t notice it if you record & play back on the same device, but it shows-up when the record & playback clocks don’t match. No clock is perfect, but a “bad” problem like that is usually the fault of your “cheap soundcard”, not the external USB interface.
You can also test your soundcard (or interface) by generating a 440Hz ‘A’ in Audacity (which will be digitally perfect). Then play it and check to see it matches an A on your (properly tuned) guitar. If it plays-back at the wrong pitch, the clock in your soundcard is off (a hardware problem).