Its not eating resources at all. My cpu Usage is less than 8% physical memory is around 37% while on game.. and yes I have disabled all audio

Aaaaaaa - I will have to quit LOL if this echo issue can't be fixed. My games all lag now and the voices keep repeating - it is really terrible. It is driving me and my friends crazy!! I am sooo sad. They don't want to play with me now .... and I really like the game
PLEASE HELP!

All you can do sadly is to disable Soun completely from LoL. Tick the option that mutes says Disable all sound. Don't try muting them individually as it doesn't give the same result.
Resort to playing without sound I guess until they care enough to fix this.

One of my friends who had the similar issue solved it by following one of the thread on the link below

http://social.technet.microsoft.com/...-b72fd8162760/

it may be the issue with the OS not the lol client. I am going to see if it will solve the problem.