Doh .... I don't know what happened. I did this mod a while back and the Xxtra worked fine in my M11. The M11 has 1 or 2 extra pins in the module craddle than the M8 had (I don't remeber exactly how many). I just drilled the needed holes in the Xxtra module in line with the existing pin holes with a very fine drill bit by hand. Monted the module back in the radio and all was good.