Runcam Split 2s control issues

fx61v320211219.param (29.8 KB)
I have been configuring AP Plane 4.1.5 on a new build over recent months. It is running on a Matek f765wse board. I have my Runcam split 2s running latest RC firmware v3.2 and the uart connected to Tx1/Rx1 (SERIAL2 in AP). I can start/stop recording fine with toggle of a 2pos switch. If I stop recording, I can enter the Runcam OSD using right roll stick. Regardless of whether up/down pitch stick is used, this scrolls down through the runcam menu items - I cannot get it to scroll up at all. Also, I have found no stick combo that will let me enter a menu - roll right does not work, and neither does rudder right.
I have attached a parameter file for ref of config. Any help would be appreciated. Thanks, Paul