|Did it ever work correctly?|
Either the sound is being echoed by another mic or by some electronic process. Any chance there is a build in mic or secondary mic?
Some effects could be from software provided by the audio card company maybe.
Might just create a new user and see if they also have this issue. If so or not you can then delete the user as it was only for tests. Delete user and files.
1/3 of highway deaths are caused by drunks. The rest are by people who can't drive any better than a drunk.