ERROR: ffmpeg: unrecognized option '-c'

[rumanoid]

I am trying to use youtube-dl on Debian 6.0.10, and I get the following error:

youtube-dl "ytsearch: Nightcall Dead V"
[youtube:search] query " Nightcall Dead V": Downloading page 1
[download] Downloading playlist:  Nightcall Dead V
[youtube:search] playlist  Nightcall Dead V: Collected 1 video ids (downloading 1 of them)
[download] Downloading video 1 of 1
[youtube] I4ArKr6W8YM: Downloading webpage
[youtube] I4ArKr6W8YM: Downloading video info webpage
[youtube] I4ArKr6W8YM: Extracting video information
[youtube] I4ArKr6W8YM: Downloading DASH manifest
[youtube] I4ArKr6W8YM: Downloading DASH manifest
[download] Destination: Nightcall - Dead V-I4ArKr6W8YM.f137.mp4
[download] 100% of 44.79MiB in 00:01
[download] Destination: Nightcall - Dead V-I4ArKr6W8YM.f141.m4a
[download] 100% of 7.52MiB in 00:00
[ffmpeg] Merging formats into "Nightcall - Dead V-I4ArKr6W8YM.mp4"
ERROR: ffmpeg: unrecognized option '-c'

[dstftw]

Update ffmpeg.