Hello,
I've been experiencing issues with extended display feature with my Garmin Edge 540 while doing triathlons. The connection works only for the very first multisport activity after rebooting the watch and thent it doesn't want to connect to the bike computer, even if I go to the sensors settings and press connect manually. This doesn't happen when I start the cycling activity, only after starting a multisport activity. I've tried different reboot combinations, re-pairing the two devices, etc. The issue occurs with auto transition either on or off.