Yeah, the SR10 Bluetooth hub. I'm still messing with it; I started by just randomly trying to tie things together, but there are all sorts of limitations to deal with. I've just started doing "rigorous testing" and writing everything down, so I should have more concrete results soon. Some of the limitations I'm dealing with:
The SR10 doesn't do stereo
The SR10 doesn't even do mono music very well, it sounds very tinny
The Zumo 660 won't pair to the SMH10 headset in A2DP-only mode
The SR10 seems to link to the SMH10 as a phone, causing problems when trying to use a phone "through" the Zumo
The Zumo won't "pass through" the SR10
One good thing, though...the SR10 does work with the Midland 75-785 handheld CB (using the SC-A0115 cable). Another thing that may work in my favor is the next firmware update to the SMH10; it's supposed to do conferencing, and I'm hoping that means that everything connected to the headset can be heard at once (no priority). When I have more hard facts, I'll post 'em.