find the max duration after handling the audio track
find the max duration after handling the audio track

longest_track[audio] is not initialized at this point

kaltura/nginx-vod-module,kaltura/nginx-vod-module,doublex/nginx-vod-module,doublex/nginx-vod-module,kaltura/nginx-vod-module,kaltura/nginx-vod-module,doublex/nginx-vod-module,kaltura/nginx-vod-module,kaltura/nginx-vod-module,doublex/nginx-vod-module,doublex/nginx-vod-module,doublex/nginx-vod-module