The module needs time to get above the noise floor before it can decode the $55 stream correctly. That is why I suggested to just look for the $55,$AA in your code; you still have to transmit the $55s before you send the $AA. Those should be considered as padding and ignored in the receiver. You may increase it beyond the 4 that you have now to improve performance if you will.
Transmit $55,$55,$55,$55,$55,$AA,"data"
Receive .................."ah there it is","data" You ignore the first 4x$55
Jerson
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