I own a Markbass 102P combo, it is actually the second one that I have owned. After about two months with the first combo it began to make a digital sounding hum. It wasn't bad power, I plugged the amp into several outlets in different locations and this did not fix the problem. The buzz seems to be only coming out of the tweeter because when I unplug the built in cab and hook up my 15" you can not hear the buzz. I took it back to GC where I bought it and they gladly swapped it out for another, which was actully the updated version with the LMKIII in it. After having this one for about two months the same exact problem has started in. Has anyone else had a problem like this with Markbass gear? I really like the tone and light weight but the fact that the same problem keeps having has sort of soured my opinion. GC says they will swap it out but I don't really want another problem amp that I will need to swap out two months later. I don't know if it is a problem with the cab or the amp. You don't hear it through the 15" but thats probably because it is a frequency that is too high for the 15" to produce, hence why I only hear it out of the tweeter. Any advice, I really want to keep liking Markbass but I tell you, they are not making it easy for me.