My MB150S started farting when I play a low F. I opened it up and found that the speaker is supported on a post which is screwed to the back of the cabinet, on top of which is a rubber foot attached to the post with a screw, which had worked loose. I tightened it up and put it all back together and it seemed to work fine for a couple of months. Then it failed again, and this time I found that some kind of rubber attachment to the back of the speaker had degraded. I ordered a new speaker from Thomas.de but found that it didn't have the rubber parts. Does anyone know where I can get the rubber parts?