Fixes crash
Fixes: flicker-1.scout3d21443372922.28.m4a
Found-by: Dale Curtis <dalecurtis@google.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit 1b82b934)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>