Locks the device to the current thread.
|lock||If FALSE, unlock the device, else lock it.
If successful, TRUE is returned, else FALSE is returned. Use BASS_ErrorGetCode to get the error code.
Locking a device prevents other threads from accessing the device buffer, including a WASAPIPROC. Other threads wanting to access a locked device will block until it is unlocked, so a device should only be locked very briefly. A device must be unlocked in the same thread that it was locked.