Quoted from Zitt:Nothing wrong with the optos.
Pulled the entrance opto, reflowed, and rewired with new wire and a 2pin connector
I’ve had the shotgun opto issue before with the 3 pros I had on route. You have an opto rx/rx issue. Reflowing and replacing the wire won’t work. Something went bad with the lense. Replace them. $4 a piece - 500-6775-01