Hello,
I suspect that this may have to do with how the IPAQ handles applications (perhaps specifically applications which are accessing hardware, which will likely be in a low power state when the IPAQ is) when it its low power state. Do you see this behavior with other applications? Perhaps try an application that does not access any hardware, and also one that accesses some other hardware. This way we may be able to decouple the issue from your Bluetooth interface, and correlate it with applications in general which access hardware during a low power transition.
Looking forward to your results and repost!
Best Regards,
JLS