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Hey guys, I'm new to all this so please bare with me.

I recently bought my first piece of gear, but I'm having some trouble with it.

I bought the Pyle Pro PDJ450U, it's a rack mountable dual mp3/usb/sd player.

I just started fiddling with it today but some things are happening that I simply can't explain as to why.

I put some mp3's on a usb flash drive, stuck it in and began to play around with it. The functions all seem to work however the audio quality is quite poor and I can't figure out why. The tracks sound great from my computer to amp, but when I put those same tracks from my computer, onto a flash drive and try it on the unit(to the amp), the quality goes way down(it just sounds sort of thin, crackly, it's hard to explain, basically just like a low quality mp3). Am I doing something wrong here? I've tried a number of different tracks, different cables, so far nothing is fixing it. Any ideas? Thanks