There's something odd here... I don't get this too often, but it's been a regular 'feature' for a long time (certainly I had the same in FS9 as I do now in X-Plane): ATC tells me to reduce speed, then immediately changes the value, then again (different speed), then again (back to the other speed again).. and goes on doing so until the speed falls below one of the values demanded. It's not like I or the aircraft react too slowly: I had four requests to change speed in under 30 seconds today (280, 290, 280, 290). Log attached. Is this a known issue?
Thanks,
Martin