Whirlpool electric oven digital selector switch issue?

Hi,
Model: AKZM 756/WH

The right-side rotating digital selector knob works fine, can select everything correctly, also the oven works most of the time, but every now and again the selected oven cooking time resets itself back to zero with its audible beep, this is an issue when we don’t know how long its been on for, have to keep monitoring/listening out for the oven to make sure it completes and doesn’t reset.

I can order various parts but can’t be sure what will fix it.

I’ve taken the top front display section off and removed the knob and separate selector switch, I assume the selector switch is the issue and a replacement is approx £30. It’s a dark crimson-red square has these things written on it:
RDE001
ROLD 150144
8.1
2027105
18891
Similar to this part from other online sellers:
http://www.europart.nl/a/brastemp-potentiometer-480121101146-amw820-amw798-akzm835-92756120
and
http://www.4whirlpool.co.uk/cooker-oven/akzm-756wh-852575638012/selector-switch/product.pl?pid=2042203&path=600151&model_ref=11368286

But before I purchase want to confirm replacing it will fix the issue, rather than it being a PCB/main board type issue instead.
I phoned Whirlpool and they aren’t much help themselves apart from the option for paying an engineer callout, they don’t do telephone support to give me an insite into what the solution is or common issues etc.

Anyone have ideas on here?