Three things: First XM & Sirius are joined so it should work.
Second, when i signed up to listem online they gave me a different password for some reason.
Third, my username was the same except it had my e-mail address at the end. Try that.
Example, My username was "wedgemoose" but once i signed up they gave me a user name of
wedgemoose@charter.com. (the e-mail i used to sign up originally)
and yes, this site rules. I wouldn't know what to do without it. EVERY question gets answered and they never get frustrated with stupid questions(like i always have).