O-360-A4A Vibration

[the4hens]

I need some help guys. I've got an RV-6 with 65 hours on the airframe and 200 since a factory overhaul. I'm turning the Sensenich fixed aluminum prop purchased from Vans. I'm picking up a vibration above 2540 RPM. Below 2540, smooth. I've turned the prop 180 degrees to see if there was a change. No affect. I recently had a dynamic prop balance and it started at .18 ips and we reduced it further to .08 ips. Flew yesterday, no affect. The spinner appears to be turning true although I have not used a dial indicator on it yet. Has anyone had a similar issue? The individual who performed the dynamic balance suggested clocking the prop off the normal "hand prop" position. Thought I'd pick the VAF forums brain before spending too much time researching.