Digital Servo Help...

[nutey]

Just getting back into 1/10th after about 16years and a lot seems to have changed

Just got a B44 which came with an associated DS1313 servo.
Remainder of the electrics are as follows:

Ansmann 2.4ghz radio gear
Mtroniks SM800 speedo (circa 1993 - pretty good in it's day)
Corally 12x3 (I think) motor also 1993 vintage. Seems to have full set of capacitors still

The car runs ok but got some servo related questions

1 The servo seems to make a noise as if a load is being applied to the steering when it's stationary and the car is on the floor - is that normal?
2 When I turn the servo quickly from lock to lock the speedo comes alive and the buggy moves forward a couple of feet - could this be due to my ancient speedo?

Brushless is not really an option for a while so need to make do as best I can...