regression: latest update fails to play some video files

Binary package hint: mplayer

The recent (yesterday?) update to version 1.0rc4-4.5.2 (package version 1.0~rc4.dfsg1-1ubuntu1) seems to have broken something, because it now gives this error

[mkv] Track 2 has been compressed with an unknown/unsupported compression
[mkv] algorithm (3). Skipping track.

followed by repeating

[h264 @ 0x7f0d58e5e020]AVC: nal size 521
[h264 @ 0x7f0d58e5e020]no frame!
Error while decoding frame!

on a file identified as having video format avc1.

After downgrading to version 1.0rc4-4.4.5 (package version 1.0~rc4~try1.dsfg1-1ubuntu1) it plays the file without any trouble. The older version identifies the file as having video format H264. Both versions try to use the ffh264 video codec.