Bizhub Pro 1051 Jamming in Duplex Mode

[salugol]

I have a strange jamming problem in duplex mode. The jam depends on the image. There is no problem for most of the copying/printing. But while printing some pages the problem occurs before printing the second side(printing the problematic page always result in jamming). the jammed paper has no problem on the first side. while passing from the ADU the jam occurs. I have tried cleaning the ADU but the strange thing is the jamming occurs only for some image which I guess having dark gray or black areas.(they are not too big <1cm2). Is there any calibration about the ADU sensors which effect this?

[ftq]

Hmm, been having the same issue, when print duplex, only jam when dark image on first side, code is j93-01, replaced sensor, still not resolve the problem , any help ?