Weird symbol in system tray

Hi, just wondering what this black symbol is in my system tray, the one to the left of the microsoft update icon. Is it a virus? if so how do i remove it?
It disappears everytime my mouse points at it.

 

I found out what it was, it was an old audio filter program i had installed before.
I went throught the steps and found one threat which was removed successfully . Believe it was called backdoor.agent.
Everything seems to be find, so thanks for the help.