Alt key to jump sessions in ACS

All,

I've had ACS on my laptop for some time (when accessing remotely) and a few
weeks ago started using it exclusively on my work desktop. Like it well.

I normally open 5 sessions. I set up keys Alt+1, Alt+2, Alt+3, Alt+4, and
Alt+5 to jump to sessions 1-5, respectively (which is what I had on the old
Windows Client Access).

A fair amount of the time when I use one of the Alt+? named above, when I
go to that session the keyboard does not respond. Every time that happens,
'File' is indented in the menu as if I'm holding down the Alt key. I press
Alt and release and then all is well. I don't remember ever having this
problem on the old Client Access. (Nor on my laptop with ACS, but then I
don't use that near as much.)

Anybody else set these keys up and run into this?

Thanks.