Last night while practicing in my home studio I encountered a strange buzzing sound intermitently coming from my Shroeder 1210 and from, (when switched) my JBL homemade cab. I quickly checked all the connections, everything was tight and working properly. I run an EBS Multi-Comp along with a Sansamp Bass DI playing thru a WW Ultra High Power. I shut off the effects and re-EQed the WW, then it all mysteriously dissapeared???? After engaging the effects again, I could not get the buzzing to occur again? Let me add that the buzzing was immediate when I struck the strings on the bass. Anyone experienced this before?