I recently bought a Pioneer 2011. I tested it at my brother-in-law's house with his Kef speakers a week or so ago. He has Q55 fronts and Q35 rears. Now this weekend he noticed a rattling noise in one of his Q55's. He phoned up his dealer (they are still under warranty) and they said the speaker had blown. They explained the cause would be a loud or strong tone being passed through the speaker. My brother-in-law thinks that the only thing that could have caused it would be the test tone on the Pioneer. Is that likely? I'm almost scared to use it again in case I blow mine, as I also use Kef Uni-Q speakers. There is no warning about speaker damage in the instruction manual and no "use at your own risk" statement. Should I think twice about using the auto calibration again? My speakers aren't in warranty so it would be a bigger problem if one of them blew. Shouldn't there be a warning on the Pioneer about it? These aren't cheap little speakers, and if it can blow them then what other damage can it do to smaller cheaper speakers? Would Pioneer be liable for any damage to my speakers as there is no warning in the instruction manual? It didn't really seem that loud though, but it did make the cone move a lot. Do you think that is what blew his speakers? Or is it just coincidence?