Proac Ribbon Tweeters Damaged


Hi all - this is my first submission, so looking forward to your responses...

I own 2.5 year old Proac D48 R speakers, powered by a Parasound Halo A21 amp (about 8 years old). When listening the other day I thought the speakers sounded dull, muddy. It appears both of my ribbon tweeters have gone out and I am at a loss to understand why.  The amp is certainly not under powered to cause clipping damage and I never play my unit abnormally loud  - maybe 1/4 to 1/3 total volume.

As you can imagine, my repair/driver replacement will not be covered by warranty as this is not considered a manufacturer defect. I am told the tweeters run $399 per.

Worst thing I can do is have these repaired and then have it happen again. HELP!
gnoworyta
almarge - thank you

shadorneb- thanks. Scary to think they are that delicate. That said, I don't recall doing anything recently in operating my set up that I have not done over the course of the last 2.5 years, in which the speakers were fine.
Growing up we had a large with room with McIntosh gear and a pair of ADS 910 speakers.  When I played music too loud, with the loudness or the bass up too high on the C28 preamp, the 910 tweeter fuse would blow.  Looking back, my father was quite patient with me.  In true audiophile form, he always asked if I could notice that the highs were absent, rather than get angry about the fuse.  
Do you have kids in the house?
gnoworyta,
Please be sure to post what the cause of the blown tweeters is after the dealer comes out.  I have a similar amp.
jetter - He really couldn't say. Although he did not "test" it, he said the amp appeared to be operating normally. He just said that somehow some sort of "system spike" had to have been generated to cause the ribbons to go.