I checked previous versions of FlashFXP and found out that in b800 my multimedia keys had worked fine, but in 849 already haven't.
You keyboard can be other than mine one: there're so much MM-boards on market, so their scancodes can be totally different.
Here's the keyboard tester:
http://www.passmark.com/download/index.htm
direct url:
http://www.wrensoft.com/ftp/keytest.exe
and my kb produces such codes:
vol up: 175 (win) x 48 (BIOS)
vol down: 174 x 46
prev track: 177 x 16
play: 179 x 34
next track: 176 x 25
stop: 178 x 36
OE start: 180 x 108
open favorites: 171 x 102
etc
You can compare to the yours one, I'm sure they will differ.
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