Recently, I've been having some issues with the auto pilot and a/c speed settings. I am using FSNavicator in conjunction with MS FS2002. Everything seems to be ok when I initiate the auto-pilot. However, after sometime (possible a certain altitude), the speed starts dropping to almost 300 kts. This happens with all my aircrafts. Also, the funny part is that this has started happening very recently. I used to have perfect auto pilot flights at 480 kts and above without any problems.I would appreciate if someone can help me with this problem. I'm losing sleep over it :-)Thanks.

Are you using indicated or true airspeed in your settings? You need to have it set on Indicated. depending on the aircaft and altitude, for example in the 737 at FL310, your IAS should read about 275 kts however your machmeter should read mach 0.74 and depending on wind, your groundspeed should be in the region of 450 kts or so.Tim