I started up Cold and Dark, watched a tutorial and did it correctly, got my FMC all loaded up, and I start flying, I have VNAV engaged and then it starts dropping to Mach .49 and keeps dropping, so I go to speed hold, and the same thing happens, then I manually apply full thrust and its only 85$ percent N1, the speed is going up, but the speed holds arent working, Im using the 757-200 and -200 Freighter, and I bought it two days ago, so its up to date seems to be working now