strange time code

Greetings transcode users.

I have a strange problem. I ask transcode to record for say, 1 minute. It
records for one minute but the actual video plays the one minute in 50
seconds!
Below is an example:


/usr/local/bin/transcode -x v4l2,null -M 2 -i /dev/video0 -y ffmpeg,null -R
0 -F mpeg4 -c  0-00:01:00 -g 640x480 -u 100 -Q 3 -w 1500 --export_fps 10 \
-J
text=pos=200x200:points=12:notransparent:font='usr/share/fonts/truetype/freefont/FreeSans.ttf',
\
fps=30:10:pre -o /videos/video_avi.avi -I 5 --progress_meter 0

tcprobe -i video_avi.avi reveals 500 frames are stored instead of the
expected 600 frames. (10 fps x 60 sec).
Notice the "-c 0-00:01:00" parameter flag.

Can someone tell me how to correct this?

 This is the 1.10rc5 compiled version.

thanks very much in advance!

Ted