Dennis, though there has been speculation on the XM forum that argon gas may cause the problem, as you can see from Randy's post, if your windows are tinted to protect against glare, the tinting is often a thin coating of metal, which could well be the cause of the signal loss. Regardless, you aren't the only one that has had this problem.

Jack

"People generally quarrel because they cannot argue." - G. K. Chesterton