Repeated dimmer failure
When I remodeled my kitchen about a year and a half ago, I installed nine line-voltage 4" recessed lights which are controlled by two Leviton Illlumatech preset dimmers, with three cans/150W on one dimmer and six cans/300W on the other (these are 600W dimmers). Everything works fine, except that when a bulb burns out there's a good chance it takes the dimmer with it. A dimmer has failed three of the four times that a bulb has burned out since the initial installation. Only the slide dimmer fails -- the on/off button continues to work normally.
Leviton has been replacing the dimmers as I mail them in, but their tech support people are, so far, unable to imagine how a bulb's burning out could cause the dimmer to fail. They've speculated that it could be a problem with a fixture or a loose connection, neither of which ideas holds water; the failures have all been simultaneous with burn-outs in different fixtures, and there are no symptoms of loose connections anywhere.
I'm hoping someone here has a brilliant insight to offer. The bulbs, if it matters, are Sylvania 50W PAR20s.