There's a few things I've noticed, that could be faults.
Firstly, there's some sort of muffled thumping sound coming through the speakers. Sounds like someone hitting something way off in the distance. It's random, not regular.
Second, the master volume has no output below 9 o'c then it suddenly comes on.
The mic channels are pretty noisy, and there's a buzzing sound that pulses in time to the play button LED.
Using the cue button to stutter a track rapidly, the sound sometimes jumps around between the speakers.
Oh, and when I press the 3rd cue button, the 4th one comes on too, most of the time.
Aparat from that lot, it's OK.....