It's odd that the USB return sounds quite good, with a bit narrower stereo field, but the stereo input (4) that I use for my synth sounds very thin and lite on bass, with pretty narrow stereo field.
I bought it mainly for use as a field recording device and I am yet to test it as such, so I might revisit this review after a while.
Undeniably, it packs a lot of features for the price, but I have to figure out the sound issue first.