Hey there, we try to print on 80g A4 duplex black&white. But the paper always got stuck before 1c in the business ready finisher. I think its the duplex area. There is no old paper left, we restarted the machine, tried different papers etc. This problems occured from one day to the other. We printed the whole day, turned out the machine, left – an when we came back the next day we could not print duplex any more.