Intermittent servo glitch

[ralphee]

OK, may have posted this before, but here we go. Using HW 2.1 XErun, with an Alturn servo on 40mhz KO propo gear, all gear works fine in any other car, except when i seem to pair it with this speedo.
It just nails it to the left every now and then when i pass through say, braking to throttle, through the neutral so to speak?
Ive swapped out Xtals, servo, receiver and all power wires are a mile away from the receiver, I've also tried a power cap, still does it,
Im told it could be the speedo, anybody had this happen? I've ordered a new 3.1 system to try now, and yes, i have updated my firmware on this unit too, still glitchy, solo, its either these servos don't like this esc, or the esc itself possibly has a BEC fault?
Reckon i should try yet another brand of servo? So far its glitched on KO and Alturn hi speed units.

lee