Sometimes especially in really dry conditions everything breaks up so bad and over loads the sieves and the seed rides out, I switched from barley to canola and never touched the sieve settings. Left top wide open and cranked the air to 690 and the pods ride out on the air and the seeds fall through. Shutting down the bottom sieve too much chokes off the air flow also. Not sure if you have 2 speed settings on the shaker but found switching to the higher speed on my TX helped a lot too.
On the CR960 I rented when excessive dry conditions loaded up the shaker they told me to open the concave and speed the rotors way up and up the fan speed too. I was told on the 9070 as long as it wasn't cracking in extremely dry condiyions they had the rotor speed up to a 1000 and do more seperating at the rotors. It seemed to work as the CR960 was picking up 30' at up to 7 mph on smooth going and got a very clean sample and shoe losses dropped way down. Kind of reverse thinking to a conventional.
Now I can't remember what the actual numbers were but the rotor was around 980 and played with the fan settings up and down till I settled for 650 with the cleanest sample and least loss. Top sieves were a couple notches from wide open and presieve was about 1/4"-3/8" and bottom about 3/8" and concaves were I think about 1.5. I finished in oats and only changes were to up rotor speed and decrease clearances as there was some rotor loss showing but monitor was still at 75% sensitivity. The sample was not as clean as my TX could do but was still good and taking 42' at about 4-5mph. Lots of straw but didn't yield great due to hail losses.