Printer slight pause during prints

Hi Guys

While my print is printing the printer will do a slight ( 2 second ) pause and carry printing. It seems to happen when it move to other parts of the print.
I have changed & bought a new USB cable & also happens when printing with the SD card.

Please could you try point me into the right direction. Very frustrating to see the pause.

Happens with all my slicers

Thanks
Vaughan
Prusa i3
Latest marlin
Ramps 1.4 Board