you have to get a hot signal on your screen, make sure the volume is up to a decent level, i like around 3/4 or a tiny bit less.
then when you plug your TT to your mpc i really recommend you use both channels, but you must first run your TT threw a mixer to amplify the sound a bit , so would run your mixer out to the mpc in's,
i always have the treshold off so you can record as soon as you push the record button,
as for sounding warped i don't know ,thats strange sounds like an internal problem but i could be wrong just try these and see if that will help you .