One of my many PBR-26D's fails update. Currently running 4.1, but unlike my other 26D's will not switch to update mode via CORE update. When I try Mobile Terminal update, MT properly detects v4.1 and does not show v4.2 available for this receiver. All other 26D's successfully updated to v4.2 via CORE or MT. This 26D is NOT in the recalled batch.

Always a bit concerned to fly an Rx that isn't playing nice

Any tips???