Every Shotcut version after 22.12.21 skipping around 0,3 seconds audio when pausing and resuming video

Bug
1

What is your operating system?
Linux Manjaro KDE Kernel 6.1 LTS

What is your Shotcut version (see Help > About Shotcut)?
Newest version is 23.07.29 for my OS at the moment.

Can you repeat the problem? If so, what are the steps?

I waited a few month now, i though maybe someone else may report this issue, but sadly no one cares… i think there was some changes with the audio engine in the last few month and in the changelogs, i was spotting some infos about performance improvements related to the Engine or Audio Engine as far i remember… but with a big audio precision trade off.

All kind of video files/formats give me problems related to the lag of audio precision. When i pause the video and play the file again, the first 0,3seconds are not played (while the video is still perfect synchron)… i think the best way to see it, is for max zoom into a file to a spott where the audio almost ends and you will experience that the last 0,XX seconds from the audio isnt playing with a newer version (Im not talking about asynchron audio/video bug) its just skips the first 0,1-0,4seconds audio somehow (while the performance is also great), this isnt the case with 22.12.21, there i have flawless and high precision audio playback.

Im a long time happy Shotcut user (i also donated a few times now to support the development) and never experienced any problems like this before and over this long periode, its a little bid dissapointing that i have to use and stay on this old App Image… i try’d all kind of other Shotcut releases, when my OS showed every few weeks a new Stable release Update (with a new Shotcut version), so i repeatly checked all kinds of versions but only 22.12.21 (AppImage) gave me, the best experience.

I also try’d other newer AppImages but without any luck :frowning:

2

Maybe we have the same problem: say my viewer is playing at 1x speed, if I press fast forward to accelerate, it skips a few frames… sounds a lot like what you’re describing I think (for me it skips a little part of the entire timeline, not just audio)

I’m on Windows and a new user, so don’t know about previous versions

3

Hmm i don’t see frames skipping, but im only pausing and play with the space button and not pressing the forward button.

Visually the player runs smooth for me (atleast without filters).

4

I am not hearing the problem you describe. What is the sample rate of what you are using where you experience this?

5

The most stuff that i edit are default 44100Hz.

Another example: You should also see it, when you pause in a conversation, if you interrupt the video while someones spelling you can’t hear the last word/character of the last spelling after resume.

If someone in a movie is saying: Bullshit and you jump back and repeat till you hear Bull then pause and unpause and you never will hear shit.

And im experience this, while the movie runs smooth and without soundcracks… and all this happends since the Engine Update.

6

OK, I tried further to reproduce it using a spoken word recording in mp3 at 44100 Hz on an audio track and playing specific words of a quickly spoken phrase like “one month at a time” and still unable to reproduce it. You say it is all kinds of formats, and I have tested with MP3 and Ogg Vorbis (as well as many types of video files). Now, I just tested 96 Khz FLAC. I tried many different frame rates in Video Mode too in case that makes a difference.

If you have Settings > Player > Use JACK Audio turn it off.
If you have Settings > Player > Realtime turned off, turn it on (did not make a difference for me, but default is on.)

I guess the reason you think no one cares is because it is not a common problem.

7

Im only edit Video files in shotcut, so im not sure if audio only lead to this issue… but i can try it out, if i have problems there to with mp3 also.

I was looking in a few videos again and i have to say my previous examples wasnt this great (sorry about that), sometimes the Audio Overview in the bottom just is delayed… like a stronger loud sound (upward curve) doesnt really fits from the graph, the audio sliders moves already to the position when i play the video but a footstep or a door slam doesnt really fits from the graphs to the actual sound that is playing.

I hope this makes sense… its just feels unprecise/wobbly somehow… normally video/sound should be asynchron from this behaviour but i don’t see anything asynchron stuff from it.

Sometimes it fits and sometimes it fits not, its really hard to describted it…

When i want to cut sound, i have more rely on my Eyes (the graphs at the bottom) in the newer version, instead mainly just listen and rely on my Ears, but i could just verify with my eyes that i cutted everything out and could make it double sure (with the older version)

The most Formats that im edit actually are mp4/mkv videos (videos only), so alot h264 video codecs with 44100/48000Hz.

fps have also big variations and they all make problems, 29.97, 23.97, 29.97, 25.0 and 59.94.

I sometimes check properties from SMPlayer (MPV Engine) to look at the Audio Stream and mostly there have aac, but im not doing anything with Vorbis or Ogg. I think this codecs are pretty old and outdated… i remember that in this codecs was famous around 2002-2012 as far i remember.

Im actually think that im edit the most used default and up to date Mainstream codecs.

Jack Audio was unchecked
Realtime was checked

Maybe, because alot people may dont care to cut precisely their content? They may don’t care if 0,1-0,3 sec audio is not cutted out perfectly… i have no idea.