I stand to be corrected here, but my understanding is that when different equipment is connected together they are all earthed through the first piece of equipment. So the problem of looping occurred because there are too many pieces of equipment each of them earthed.
The solution is disconnect each piece of equipment in turn until the problem is solved.
Everything should be safe because as stated above each part is earthed through the previous piece of equipment it is connected to.
Start by disconnecting each piece from the end of the chain.

[This message has been edited by Graham UK (edited 03-10-2005).]