trouble with my analog moog delay

[snuepz]

my moog analog delay is acting funny. i just got it around 6 months ago from music toyz. basically it starts off fine. but then if i turn it off then maybe a few minutes later switch it on the delay does not work. when the green light is on. another thing happens sometimes is that you will hear a delay sound but if i move any of the knobs nothing will happen to the sound. if i unplug it and then plug it back in works fine again. it doesnt happen every time i hit the foot switch but at least once or twice through out the course of a performance. please let me know who i need to talk to. thanks john