PCI-DIO-32HS error FFFCB820 (-215008)

DAQmx Start task gives this unknown error. What can it mean?

I am running digital acquisition task  with Burst (Output clock) with some external device, transmitting data. Alone it works fine.

Then I need to measure time after the read ends (PFI6 = Dig0/ReadyForTransfer falling edge) to external digital edge coming to PCI-6602..

If I configure (route /DIO/Dig0/ReadyForTransfer to RTSI2, setup counter measurements on PCI-6602), while DIO task is running (starting, measuring, stopping) both tasks run fine.

But I need to synchronize them.

If I first configure HSDIO task,

Then make route, configure and commit counter task, configuration  works fine.

But DIO-32HS Start task gives above error.

Is it because of some route that is required for DIO task, but is blocked by PCI6-RTSI2 connection?