android Bluetooth connection loses messages
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I have added Bluetooth two player support into my game.
But almost half of messages is being lost.
The distance between devices is a few cetimeters.
I am disappointed.
I  send 100-2000 bytes per second (up to 15 kbit/s) 
What to do? I can add confirmation for each packet.
But confirmation packets may also be lost.
Should I calculate CRC for each packet? 
I can send the same 3-5 packets.

My bluetooth is based on Google's bluetoothChat example.
Thanks.

