Sorry, still no repro. I type "wondows" (which ends up selecting windows anyway because it's the only entry with a W), then press home which returns it to the first item in the list, then "windows" which selects windows again. There's no beeping at all.
I repro'd it, but it only happens if you start typing stuff, then press Home, and then press another key really fast. I can barely do it on my laptop's keyboard because I have to hold the Fn key in order to hit Home. Even on my desktop the time it takes
to move my hand to the Home key is long enough for the type ahead to reset.
The behavior changed because the list view control used in the Win7 Explorer is a brand new control written from scratch. I'm guessing the old behavior was just a quirk of the design, but I wasn't around then, so maybe it was intentional. I'll mention
it to the people who own that new control, but unfortunately it's a bit late to change anything that doesn't impact a significant number of people (and that has an easy workaround... just hit Home and then wait half a second or so until it resets).