Popping sound from powered speakers - HELP!!! 
Hey everyone, I am currently having a problem with my rcf 312a speakers, it seems every time i turn them on there is a really aggressive, popping sound that is really loud. It happens when there is no sound flowing through from the mixer but it will continue if i play anything, possibly grounding problem? 
if soo could someone please elaborate and suggest a soultion? I bought them from the thomann website (they have the european 2 pin plug), Im from ireland so i have had to use a plug converter to suit uk/irish plug. Also everything is powered through one socket with the use of adapters maybe this is a problem, however I have plugged it into an alternative socket and still the problem persisted (infact a buzzing sound occurred prior to the speaker popping).
There was literally no problems with these speakers until a few weeks ago when the one i was using started to pop like crazy 
i wasnt in the room at the time but soon heard it. It was resting on the other speaker (not in use at the time), could that have possibly triggered something via the metal, magnetism etc … ?? could it be the wires connecting even though they are relatively newish and havent been used that much at all. Also the speaker in question has been used very little maybe 2 gigs and jus when im playing it low at home. Im gonna try the other speaker its under wraps at the moment to see if the problem is isolated to just this speaker or if is the two of them 
Anyway i know theres alot there for somebody to take the time to answere it may just be something simple or i may have to send them bk to thomann, any help would be greatly appreciated