Thorsten,
The loopbacktest is good, but with te same delay :pinch::( Yello Led continu after short time red led also continu with delay after last signal that sending.
But if i have the ribbon cable, J4 to J2 in the hand than is the delay much shorter. if i have to leave the ribbon cable the Delay is the same long time. Its not a broken conecting.
Best Regards,
Koert