Originally Posted by jpollard
Root by definition is a member of any group it wants. Adding root to random groups is an invitation for a security failure.
I agree with both jpollard and notKlaatu.
notKlaatu *DID* provide the answer to the question, but the OP is asking for something that is inherently bad. Logging in as root shouldn't be done, period, unless you're trying to fix something seriously bad. And I doubt you'd need a sound card for that.