Pitch change on playback

[msantarc]

I've been using Audacity for quite some time now. I recently bought a new machine and it came with Windows 7. I've made some recordings with no trouble, but twice, after recording sever tracks (3-4) an additional track will record (or playback) in the wrong key. It's as if the software has changed the pitch. The backing track still plays fine, but the newly recorded track is off key. Any ideas as to what might be causing this? I seem to have to reboot to resolve the problem.
I have 12gig of ram so I don't think it's a memory issue.
Mike

[steve]

It's most likely the sound card.
Are you using an on-board sound card?

You could try changing the default sample rate - most on-board sound cards work best at 44100 or 48000 Hz. Ensure that the default sample rate in Audacity matches with the default sample rate for the sound card in the Windows Control Panel.

[msantarc]

It's most likely the sound card.
Are you using an on-board sound card?

You could try changing the default sample rate - most on-board sound cards work best at 44100 or 48000 Hz. Ensure that the default sample rate in Audacity matches with the default sample rate for the sound card in the Windows Control Panel.

Thanks Steve, I've got a Line6 UX2 guitar/mic interface connected that takes the place of my ob board sound card (realtek HD Audio). I'll have to do some research to see what the sample rate is for it.
Audacity is, and has been, set to 44100. The sample format (what ever that is) is 32 bit float.

[steve]

Leave the sample format in Audacity at 32-bit float (that gives highest quality editing and processing).

As it is a USB device, another possibility is that the USB could be playing up. Avoid using other USB devices at the same time - don't use a USB hub - if your computer is a full size PC, try connecting the USB cable to one of the USB sockets on the back of the machine - avoid over-stressing the CPU while you are recording.

The Line6 UX2 will go up to 96 kHz sample rate, but I'd suggest that you try it at 44100 Hz / 16-bit and leave the Audacity settings as they are, then see if the performance improves.

[msantarc]

Leave the sample format in Audacity at 32-bit float (that gives highest quality editing and processing).

As it is a USB device, another possibility is that the USB could be playing up. Avoid using other USB devices at the same time - don't use a USB hub - if your computer is a full size PC, try connecting the USB cable to one of the USB sockets on the back of the machine - avoid over-stressing the CPU while you are recording.

The Line6 UX2 will go up to 96 kHz sample rate, but I'd suggest that you try it at 44100 Hz / 16-bit and leave the Audacity settings as they are, then see if the performance improves.

Any idea where I change the UX2's sample rate? I looked in the Windows Control panel and the info under the UX2 device didn't seem to include the ability to change or even see the sample rate.

[steve]

I don't have Win 7 or a UX2, but have a look in the "POD Farm 2 Recording Setup Guide", section 2.19 "Windows® Driver Settings"
(available from http://uk.line6.com/support/manuals if you don't already have a copy.)