I had not notice this sound until using a single bluethooth ear piece at work. So, this is what a bong rip sounds like? They should have panned it left- right - left I think - and cut the low-mids, boosted the high/mid mids and eq'ed the mid highs to sound a bit more middy - would have made this tune #1 all day long!
I assure you, it air bubbling from a bong. What he say around 2:50 when that section of the song commences?
I'm pretty certain it is George's car...he was probably delivering the goods (Sorry Mr. Halford - I could not help myself)...