IDR-8 factory reset defaults

Hi All,
I want to reset an iDR-8 that has been serviced ad we have no history of previous technician whereabouts and need to start fresh.
I’ve had little experience with these.
Just wondering if these are basically an 8in x 8out matrix mixer (routing wise) out of the box or is it a big learning curve?

Thank You

Update-
So I got into the programming and cannot see where the input select (left hand row of 8 buttons) are configured.
on press, the left buttons scroll though the selected inputs indicating on the leds but it skips channel 2 and 8 and I cannot see where these channels have been dropped in the programming.
the manual has an edit module “manage iDR Patches” but there is no instance of this on the edit menue (iDR System manager V3.73

apreciate any advice.. thank you

go.png)