Tested this site: http://www.angelfire.com/fl5/html-tutorial/a/couldyou.mid (quicktime) No sound in Firefox. Tested youtube. (shockwave flash) No sound in Firefox. Tried uninstalling and reinstalling firefox. Tried uninstalling and reinstalling everything Adobe/flash. Tried system restart. Tried system shutdown and restart. Cleared all kinds of history for today (when the problem started). Going to try a new profile in about thirty minutes. Going to try safe mode in about thirty minutes. If you don't see another post in 45 minutes or so (5:30PM JST, Sat. May 29, 2010), it means a new profile and safe mode didn't help.