they narrowed it down to a current limiter issue.they tested my speedo every different way thats what they come up with. that night when I was there two other guys had the same issues. One was able to fix it by running an external bec and worked perfect. It feels like a bad sensor wire, or cogging when punching full throttle,doesn't happen when you roll on the power. I've been wating for these speedos for a while, come to find out I'm able to run the Pro4 4000kv with the TC spec and is flawless!