Our application has an XBEE PRO S1 (in API mode) paired with one or two others. Our communication protocol recently expanded so that we send three 6-byte messages from the XBEE in API mode to one of the other XBEEs. Often, the first two messages are received but the third does not get through. Is there any history on this? Are there any conditions or configuration issues that can cause this? And, if so, are there work-arounds or fixes?