Hi Lee.
can you provide some more logs from emonhub of when the fault occurs, we can’t really pick out a pattern or base a diagnosis on the one occurrence.
It could simply be that the rfm69’s stronger receiver is pulling in more interference/noise which it is discarding but in the time it takes to receive and determine a packet is garbage, it may have missed a good one.
You could try updating the rfm2pi’s firmware as JeeLib has been updated and I believe the rssi threshold has been revised so a significant chunk of those weak packets could be discarded sooner in the process and hopefully catch more good ones. You should recompile your own copy or use this test firmware (taken from the RFM69Pi stops updating/freezes thread started on the old forum)
The issue with the example packet is a different thing as it failed crc and has a good rssi, so it maybe that you have more than one issue, perhaps this pre-dates the swap to rfm69, but you were unaware as enough packets were getting through.