DWM1000 Double Sided Two Way Ranging Example 5

I have been working on Example 5 ds_twr using a DWM1000 and arduino uno.
The reported distance seems to start at a value and increase/decrease as more measurements are taken.
What is extra strange is that if I have a small delay in between each twr exercise, the reported distance will decrease (from its initial value) until it reaches a steady state. Conversely, if the delay between each twr exercise is larger (maybe 1000ms) then the reported distance increases from its inital value until it reaches a steady state.
I initially thought the problem was that the clock on one device was running faster then the clock on the other device, however since the distance algorithm uses differences in time measured on each device this should lead to an error in the distance measurment but not a increasing/decreasing measurment between ranging exercises.

Hi @BigMac,
While I cannot really assist you in your doubt, as I myself am a beginner with these modules, I wanted to ask whether you could please provide some details on how to use DWM1000 with Uno. I wish to use this for my project but all sources seem to mention that only Arduino Pro Mini works with this.
Thanks in advance,