hello, i'm using a boss gt 10 multi-effect connecting via usb cable to my comp. i've read somewhere that it has an built in sound card, however when i try to record i get go sound in my headphones but low quality in the record. i don't have an external sound card. do i need to buy one or am i doing something wrong with the boss?
Have you read the manual? It has comprehensive instructions on how to setup the USB connection. It's on chapter 7, page 90.

Here's the link to download the manual in case you need it:

On a side note, you'll probably get a better recording quality by mic'ing up your amp, then using an USB/firewire interface to connect the microphone to your computer.
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