I've built half a dozen bikes, so I'm somewhat experienced in this department, but this one baffles me.

SRAM Red (road shifters), 10-speed, not the yaw version. Not a tremendous amount of miles. I moved this groupset from an older frame to a new R3 frame.

I setup the high and low limits perfectly. I put it in the stand, on 52x11 and shift up. I tighten the barrel until it shifts up and stops clicking around. I shift up and down the cassette, everything seems fine. Until I get near the top of the cassette, one gear from the top. It grabs the chain, and tries to shift it up to the largest cog.

Ok, tension is too tight. So I loosen the tension until the 2 biggest cogs are working correctly. But then back down towards the 11-tooth cog, it shifts like garbage again. It's always either too loose or too tight, with no in-between. I can set it up to work perfectly with the smallest cogs, or with the largest cogs, but no in-between.

I'm using new cables, newish cassette, and pulled on the cable while shifting to confirm the cable is moving smoothly. Hanger seems straight and tight. I'm not sure what to do next.

Thanks guys and gals for any input.