Originally Posted By: tfabris
..such as crumbling foam speaker surrounds..


If it does turn out to be crumbling foams, replacing the foams is quite easy to do oneself. The foams are readily available for $2-6/pair from Asia (eBay), and a bottle of suitable glue can be picked up at any craft store -- I used "Aleene's Original Tacky Glue" on two pairs of speakers here.

Cheers