Hi Miko,
digital servos are making 99,99999 % some little noise in centre position, that is normal.
100 Hz or the 17ms, AUTO setting etc. has nothing to do with the noise of digital servos in centre position; but more whit smooth running of the servos.
If possible I would always suggest to use one typ of servo or servos from one company. My personla opinion is that a mixture of servos from different companies is not perfect.
So I would use all MKS or all Graupner servos in the plane.
Regards
PW
Rechtsbeistand u.a. bei "Modellflugproblemen"etc. : Rechtsanwälte Wessels & Partner, Tel.: 02362/27065
PW Modellbautechnik ( Jeti Kombiangebote, Beratung/Einstellservice etc.)