Pete, I have been through the Air Hauler forums and they  have talked me through a  whole load of things and they  say that it must  be the  FSUIPC as when I did a clean install  of FX everything worked fine until I ran the Air Hauler program through FX and after  that  FX was screwed up even  when  not running Air Hauler. The Air Hauler forum have told me that AIr Hauler uses FSUIPC to  communicate with FX. so  when it installs it  installs FSUIPC as  long as it just  sits there dormant its  fine. Once I run  Air Hauler once thats it FX will not  work with my yoke. I have copied the log files to see if this can tell you anything. this  was done with just  FX flying  a default  cessna until  my yoke froze  on  me. 
********* FSUIPC4, Version 4.50 by Pete Dowson ********* 
User Name="" 
User Addr="" 
FSUIPC4 not user registered 
WIDEFS7 not user registered, or expired 
Running inside FSX on Windows Vista (using SimConnect Acc/SP2 Oct07) 
Module base=61000000 
Wind smoothing fix is fully installed 
DebugStatus=0 
      140 System time = 09:41:36 
      140 FLT UNC path = "C:\Users\Debs\Documents\Flight Simulator X Files\" 
      140 FS UNC path = "C:\Program Files\Microsoft Games\Microsoft Flight Simulator X\" 
     1170 LogOptions=00000000 00000001 
     1170 SimConnect_Open succeeded: waiting to check version okay 
     8548 Running in "Microsoft Flight Simulator X", Version: 10.0.61637.0 (SimConnect: 10.0.61259.0) 
     8548 Initialising SimConnect data requests now 
     8548 FSUIPC Menu entry added 
     8611 C:\Program Files\Microsoft Games\Microsoft Flight Simulator X\FLIGHTS\OTHER\FLTSIM.FLT 
     8611 C:\Program Files\Microsoft Games\Microsoft Flight Simulator X\SimObjects\Airplanes\Aircreation_582SL\Aircreation_582SL.AIR 
    32136 C:\Program Files\Microsoft Games\Microsoft Flight Simulator X\SimObjects\Airplanes\C172\Cessna172SP.AIR 
    48687 C:\Users\Debs\Documents\Flight Simulator X Files\VFR Shannon to Glasgow.PLN 
   101478 System time = 09:43:17, Simulator time = 13:15:41 (12:15Z) 
   103990 Advanced Weather Interface Enabled 
  2066935 Sim stopped: average frame rate for last 1966 secs = 13.8 fps 
  2072379 System time = 10:16:08, Simulator time = 13:48:26 (12:48Z) 
  2072379 *** FSUIPC log file being closed 
Average frame rate for running time of 1966 secs = 13.8 fps 
Memory managed: 889 Allocs, 889 Freed 
********* FSUIPC Log file closed ***********