Altering Firmware settings for Heat Bed calibration + boosting bed current?

Is there a simple way to alter the calibration levels for the heated bed and maybe increase the drive current a little? My upbox bed seems to be out by 10 deg C when compraing Upstudio temp with calibrated digital IR thermometer.

Upping the drive current a little to might help with be heat times.

Failing that anyonoe have any good mods to boost the heating power of the bed a little