When using the Advanced Bluetooth audio service, BlueSoleil (V10) turns out to change the Windows default audio device for audio playback. This seems to happen after reboot and when resuming from sleep or hibernation when an A2DP connection exists while Windows is suspended (put to sleep).
This is very annoying, because this also effects other programs, even those that even don't use Bluetooth: So please don't do this!
The device that is selected seems to be the parameter that is specified as the output device on the Options tab of the Advanced Bluetooth Audio service properties sheet.
By the way, when opening the selection box to select a device for this purpose, there are one or two empty lines. Don't select one of these lines, because it will crash Windows on every startup of BlueSoleil from than on. The only way to undo this is, is starting windows in save mode and un-install BlueSoleil.