Cant be 100% sure its ADR related, basically I’ve been switching between the MCCI lmic build and matthijskooijman/arduino-lmic. I’m using standard code, nothing unique and switching between the two libraries - the MCCI library is somehow causing random crashes on the node - sometimes with error codes other times is just hangs. If I switch to matthijskooijman/arduino-lmic all is smooth and this tick along just fine.
I will raise an issue in github rather than hijack this thread.