[chirp_users] FT 857 upload problem

Greetings all, Using version Daily - 20201014. Linux Ubuntu Mate V 20.04. CAT - USB lead. Cat speed to 9600. Image file of radio saved if required. With FT817ND download and upload OK. With FT857D download OK. Carried out widebanding by solder jumper method. Memory image file upload fails, reports 'radio did not ack block 0'. Connections and lead seem good, FLRig controls the 857 OK. Original Yaesu CAT62 lead tried with serial to USB adapter, no change. Chirp bug 3081 of 2015 similar case but resolved by sender, no details. Any help appreciated. John G4BLJ