All sorted, I purchased a thermaltake 500w PSU with a 110/240 switch on the back and it worked.

It seems that the Automatic converting PSU's do not like the RFM, I tried 2 Antec 500w auto switching PSU's (2 differnt models) then another cheapish auto switching one as well and they all gave me the the reboot at different stages of pressing any buttons on the RFM.

I then tried the thermaltake with the 110/240v @ 110 switched on the back, installed it all again for the 50th time   and it hasn't skipped a beat since