The 7350 has the black "DRO". It could be the DRO or the end block need a slight adjustment. It comes apart fairly easily if I recall. I have a 7350 as well. The unit shouldn't be super stiff - it needs some adjustment.
Be careful when single pointing, it is possible for the compound DRO to foul with the cross slide DRO unit. Yes, I did that. Must not have been paying attention... Buggered it up during the pandemic, and there were no spare parts to be had. I machined a temporary solution which held up for about 9 months before it failed. Basically the brass insert in the plastic DRO head pulled out. I have since been able to get a replacement DRO head so all is well.