One of the people I know that has this happen to him is racing 1/12th 1 cell, he is using a receiver pack and still having this problem.
I'm racing 1/10 th Sedan with a 17.5 2 cell , why should I have to add/try a receiver pack ?
to solve a software / hardware problem the manufacturer should be responsible for ?
Time to just sell that Speedo and buy a real Speedo... Everyone I know who bought a CC speedo was not satisfied with the performance/ consistency...
This was a few years back and I guess nothing has changed.