Well, I misread the FAQ when I purchased the mount - I thought I was getting a mount which could also output audio through a jack; I didn't realize that the 2100 and 2500, which do this, are not Treo 650-compatible.

So, has anyone gotten crafty and modified the mount to add a 2.5mm plug, where it appears to have a mold line where one should be? I'm considering using the Belkin 90 adapter, passed through a hole in the cradel socket, and sticking out the left side of the lower shell, and wonder if anyone has insight into this process and its success. Thanks!