I have an MTD with a Bart single MM pu and Aguilar OBP-3. Sounds great, no hum, but there is one venue that I played in Austin Tx that gave me some trouble. All y'all that have played at MOMO'S with an active setup and had this same problem, please join in. And this noise is an intermitant pop-tick that is not consitant or regular at all. Amplitude varies as well. I had a passive P bass at that time and it did not have the same problem. It was plugged into an SWR Workman 10 and then DI'ed into the system. I disconnected the DI but the clicks were still present. I contacted Aguilar and they responded thus: "This would make me suspect radio (RF) interference, then. And the reason is this: semiconductors can be more susceptible to RF interference than passive electronics, and in the case when there are electrical sparks (like when certain relays and switches are used to turn equipment on and off) there can be large bursts of RF interference that can manifest as pops. So for example, let's say this place has an AC system that turns on and off automatically, and that the switch is near the stage, this could cause the problem. Also, as I understand it smokeaters and bug zappers also produce large electrostatic events that could lead to RF bursts if they are not properly grounded and shielded. These are guesses, and I don't have a solution for them except to say that shielding should take care of RF problems. I assume that your MTD is shielded, but perhaps there is room for improvement. However, if there is equipment in this club that is not properly grounded and shielded, it may still get through your best shielding efforts...First, don't write off static discharge. Even with your hands on the strings you could be having static problems. Next time you're there can you lean against a pipe or stand perfectly still and see if that makes a difference. I know that sounds silly, but I use a rehearsal studio where the isolation of the floor gives me some static problems that can be solved this way." I did the lean against the pipe thing and the noises still were there. I don't have a passive switch to test and I no longer live in Tx, but if it happens again I would like to know if there is something I could do to eradicate the problem. Any thoughts would be appreciated.