Zute, as I started to read your post my immediate suspicion was that a loose strand of connecting wire was vibrated into contact at certain frequencies/sound levels causing a short and shutdown. Then I read that this didn't happen during movies, so the strand of wire causation seems unlikely, although the connections should still be carefully redone.
I can assure you, however, that there's no general difficulty in driving the M22s with amplification even more modest than what you used. Years ago I tested my "3 ohm"(around 4000Hz) M22s with the 4064Hz track from a test CD and had no problem with extended play at that frequency at a higher than normal sound level. This reinforced the conclusions I'd drawn from a study of technical literature which indicated that concerns about low impedance were often grossly overdone.
I've had no problems with my M22s for 8 years now, and suggest that you're not likely to have any either.
