Thanks for your post and welcome ,
It seems you may be onto something , however win 7 64 Bits is not supported at this stage by our version of ffmpeg nor by earlier versions of QMC. This could explain why it is giving you strange results ...
Have you updated lately your OS to windows 7 ?
Also please inform us more on the technical aspects of your input file ( click right on it in QmC and copy paste the technical information here please) .
Did you try to change the ratio in expert mode as well using profiles ? you may want to try that possibility if for some reason the command line is http://www.cocoonsoftware.com/paypaldonate-us.htm .
We are looking forward to your news ,
Have a nice day ,
thx for donating