We did Murmur last night after about 5 or 6 attempts, even I was rdy to throw the towl in and starting to get narked :mad:
The team we had was Lasiien, Saxif, Aphaia (rogue), Razien (warlock-demo), and Taurenmuscle (warrior).
We had TM stay in combat at all times with it, when it aoe'd Las (i think) put a shield on him and the rest of us legged it.
Aphaia has Cloak of Shadows which made her immune to one of its aoe's, and I think she used dash/sprint to get out of range of another.
Myself Las and Raz where all very aware who had Touch of Murmur and when it was on us we made sure we moved away from each other.
Myself and Raz took turns in sending our pets into melee with Murmur after it had killed TM and Aphaia to stop it launching multiple resonance bolts at us, I think we used 3 pets doing this, but as long as someone/pet is in melee with it then the damage it dos to the grp is lessened (no bolts).
It still took everything we had to kill him and only 3 of us were left alive when we had finished and I died just after due to Touch of Murmur, but we downed him, barely. Although good gear helps, its really nailing down the right tactics to use that allowed us to finish him off.
I think that melee's who need to run out should maybe try and get some potions of haste to speed them up, although then they won't be able to use potions of healing so ... If ppl still have the Nifty Stop Watch (quest reward in Burning Steppes I think) might be worth equiping that to help them get away also.
I know it can be done both ways, as Xanic has done the running away approach, but this seemed to work well and allowed us to keep everything under control.
If we were to do the running away approach then pet classes could send in pets (alternating) to keep something in melee with Murmur when tanks r legging it so he doesn't start kicking out Resonance Bolts. I don't actually know if a tank can run out of range of his aoe without some kind of buff, but maybe when your melee'ing him it might be worth fighing inside him facing the grp so you can just run directly forwards in the future, assuming that works?
Just some info and thoughts for the morning

Sax.