servo continues to sound after stopped movement

I have a Prusa i3 with RAMPS 1.4 and have now installed auto bed leveling on it. When I'm trying it out the SG90 servo moves ok but continue to make ticking sounds after the movement is finished. The sounds keep sounding until I push the stop button on the LCD panel.

Is this a problem I should be worried about or is it common?
I have cut the original cords and soldered extensions to them. Could that create this problem? For the installation I have followed ZennmasterM's setup guide (https://www.youtube.com/watch?v=awsI9bMndJA).

Thank you for your help!

Edit:
I can now also add to it that the sounds start already when I just connect the computer to the printer and only stops when I press the stop button on the LCD panel.

Edited 2 time(s). Last edit at 09/29/2014 10:04AM by Roberth.

some servo's are a little different...

You may have to edit the servo.h file to stop the chattering.
most likley in this section:

#define Servo_VERSION 2 // software version of this library

#define MIN_PULSE_WIDTH 544 // the shortest pulse sent to a servo
#define MAX_PULSE_WIDTH 2400 // the longest pulse sent to a servo
#define DEFAULT_PULSE_WIDTH 1500 // default pulse width when servo is attached
#define REFRESH_INTERVAL 20000 // minimum time to refresh servos in microseconds


I think it's this section...
these are the pulse widths to adjust forward and backward and still positions...
be careful with these though, and perhaps adjust them with the servo out of the housing, because if the still setting is changed, it may creep...
the chattering noise you here is it on the verge of creeping if I understand correctly...

Edited 1 time(s). Last edit at 09/29/2014 10:44AM by Waltermixx.

Thank you for your answer.

Should I increase or decrease it? Is it the default I should change?

I believe it would be the default...
try increasing by 10 first, see if the buzz is louder...
if it is, then decrease by 10 and check it again...

may be a bit of trial and error...