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!