tmproff,

SteveV was talking about GAMEPORT interface, while you seem to be referring to a serial port interface. There's no "baud rate" setting for gameport, AFAIK.

I started thinking about different cause of this problem after one of my computers started showing similar simptomps. That PC was working just fine with a gameport interface, when it started glitching recently. Nothing changed either in PC hardware or in interface or in transmitter. If I take the same interface to my other PC (an identical computer with the same hardware, just much less software installed on it), the interface is silky smooth!
So, it looks to me that after too much tweaking with Windows XP (installing and uninstalling different software, changing OS settings, etc.), Windows itself came to a stattering state, when any application, not just R/C sim, gets interrupted by some strange activity. I'm inclined to think that this is not a virus, as I'm running Norton Antivirus all the time. It isn't Norton Antivirus itself as it didn't cause trouble before and, when I disable the antiviruses, glitches persist.
If I strt the TaskManager, it shows that System process occasionally grabs a lot of CPU time. I can't think of what's going on: some network activity, disk indexing, or something of this nature?

Too bad I don't have time right now to re-format the hard drive and make a fress installation of Windows XP. I'm sure that this will eliminate the glitches as an identical PC with same Windows XP and same TX/interface works flawlessly.

Trying to solve another Windows mystery,
Boris