Just take anything fire based (or whatever) and reduce all the damage die sizes by 1, change all fire to sonic, replace any skill bonuses with bonuses to listen and maybe move silently (you know how to NOT make sound when you wish... or even have a dampening field you can create a few inches from your skin).


Alternatively, here is a very sloppy on the spot homebrew:

Half-Warsong Dragon
Type Changes to Dragon
Immune: Sonic, Sleep, Paralysis
Str +2, Dex +4, Con +2, Chr +2
Breath Weapon: 1/day, 6d6 sonic damage, DC 10+(HD/2)+Con Mod
+4 racial bonus to the following skills: Listen, Move Silently, Perform (Sing)
+2 racial bonus to Perform (Oratory)
Bonus Feat: Energy Substitution (Sonic)
Level Adjustment: +2


That should be both more playable, and more thematic than a half-howling dragon. Throw in a feat or two for blindsight at higher levels (probably based on a Listen ranks requirement), and it should be pretty good.