First of all it's not going to show a constant temperature. Even after it turns off the temp continues to rise because the element is still hot. Then when it turns back on it still continues to drop a bit because the air was cooling and engaged the thermostat.
With that understood, the trick is keep it midway between the high & low. Mine dips to 99.4* and peaks @ 100.6* so figure the ave temp inside the eggs is 100*. That's measuring with the remote sensor at top of egg height in the middle of the bator near where the fan blows.
Your 103* would concern me because that's too hot. You should stop tilting it if that whacks the temp and then you could probably keep a more consistant & uniform temp.
And another thing, the wafers are super sensitive to changes in barometric pressure so when the weather changes it whacks the temp, by about .5* either way depending on if it was a high pressure front or a low pressure front.
Just find 1 accurate thermometer and go with it. Using multiple thermometers in various locations and constantly tweaking the temp adjustment will drive you insane.
Hope that helped.