I had the same problem with my Paradigm Sub. I had it's amp repaired under warranty. Down the road it broke again, this time out of warranty. This time I took a peek behind the speaker cone and found that the bare wires from the back of the cone to the terminal board were intermittently touching together causing the amp to blow again. I talked to someone else with Paradigm Speakers and his receiver was shutting down. He ohmed out his speakers and found one shorted. I told him to take a peek behind the cone and there it was, the bare wires were touching. Things are good for him again.
So you may want to take a peek there too. I hope it's just shorted wires and not a blown amp. Good Luck !
(LCD - Sony KDL - XBR4) (Receiver - Sony STR-DA4ES)(Blu Ray - Oppo BDP-83) (PS3)( Dish Hopper DVR With Sling) Speakers (L & R - Paradigm Studio 20) (Center -Paradigm CC-470) (Surrounds & Back Surrounds - Paradigm SA-15R in walls) (Subwoofer 1 - Sunfire HRS-12) (Subwoofer 2 - Paradigm PW-2100)