Temperature fluctuating... but print is good

What is the problem?
I start a print. Slicer S3D. Temp bed:60 temp tool: 225. Fila: petg. Temperature of the bed fluctuate between 59 and 61.
But the temperature of the tool fluctuate from 220 to 230. That is 15 from the temperature I want.
I have also seen that it jumps from 230 to 219 and then back to 222.
The print stays good.

What did you already try to solve it?
I ran more than once that pid procedure. Everytime I choose the temp which I am going to use for my next print.
My cr10s has the original motherboard.
I have also bought the direct drive system of Bondtech.

Additional information about your setup
I think the showing of the temp is not correct by octoprint. I have the latest version.
But how can I be sure there is nothing else?
I want to anticipate....

OctoPrint gets its temperatures from the firmware via a temperature report initiated by either an M105 command or an M155 command which tells the firmware to send a temperature report every so often.

If you enable the serial.log, you can examine the temperature reports yourself and I'm pretty sure you will discover that the fluctuating temperatures are being reported by your firmware, not being "invented" by OctoPrint.

Thank you, b-morgan, that is a good start.
But then is the question do I have to update my firmware (Marlin 1.1.9) for this or will it be better to do something more (e.g. change motherboard)?

You have checked to see that the thermistor is firmly attached to the hotend?

If it is, then the next thing I'd do is find a Creality forum (i.e. one with lots of CR10S owners) and ask them.

Assuming I didn't get a good answer, I'd try an updated version of firmware. Assuming that didn't fix the problem, then I'd contemplate obtaining a different board. I might try a replacement thermistor first, however.

Thank you very much for those tips. I know what to do in the weekend.....