out of phase audio track channels

The issues found when using the Show Manager panel
kenact
Posts: 432
Joined: Thu Apr 23, 2015 6:43 am
Real Name: Ken Coughlin

I'm sorry, but I still can't replicate your problem.

What are the specs of your video file, and which codecs are you using?
thibaultphil
Posts: 49
Joined: Wed Nov 04, 2015 10:22 am
Location: Blois - France
Real Name: philippe thibault

Thank you for your investment.
The video file is to be produced in mpeg, I used this file to take into account the resolutions proposed in the post viewtopic.php?f=22&t=12357&start=20 but it does not is not necessary because does not solve my problem.
kenact
Posts: 432
Joined: Thu Apr 23, 2015 6:43 am
Real Name: Ken Coughlin

I was asking how big your video file is.

What is the resolution?

How long is it?

What codec package are you using?
kenact
Posts: 432
Joined: Thu Apr 23, 2015 6:43 am
Real Name: Ken Coughlin

I'm sorry, but I still can't replicate the problem you're having. I added a video file, to represent the video in your project, and I used FormatFactory to convert your MP3 to a WAV file.

The cymbal crash comes at 18:09 consistently, whether I play it in Shows or Virtual Console.
thibaultphil
Posts: 49
Joined: Wed Nov 04, 2015 10:22 am
Location: Blois - France
Real Name: philippe thibault

I ran my project on an old windows 10 tower pc in version 4.12.3 and 4.12.6 and everything works fine. What system did you perform your tests on?
For me the problems appear on 2 Windows 11 laptops.
thank you again for your investment
User avatar
edogawa
Posts: 630
Joined: Thu May 07, 2015 10:34 am
Real Name: Edgar Aichinger

My laptop is about 10 years old - a low end Asus X756UJ notebook, with 4x i5 6200U@2,3GHz
couldn't reproduce on current openSUSE Tumbleweed nor Windows 10 22H2
kenact
Posts: 432
Joined: Thu Apr 23, 2015 6:43 am
Real Name: Ken Coughlin

I don't have any Windows 11 computers to test on. I have been testing on Windows 10, on a 15 year old laptop, a 10 year old laptop, and a 7 year old tower. It sounds like Windows 11 is the culprit. What laptops are you using? Are you using the on board sound, or an external sound processor?
thibaultphil
Posts: 49
Joined: Wed Nov 04, 2015 10:22 am
Location: Blois - France
Real Name: philippe thibault

I am using an HP windows 11 laptop from 2018, an HP windows 11 laptop from 2021 and an HP windows 10 tower from 2011. Only the windows 10 laptop is working properly. I use the built-in sound.
User avatar
mcallegari
Posts: 4710
Joined: Sun Apr 12, 2015 9:09 am
Location: Italy
Real Name: Massimo Callegari
Contact:

Which audio card are you using when experiencing the issue?
thibaultphil
Posts: 49
Joined: Wed Nov 04, 2015 10:22 am
Location: Blois - France
Real Name: philippe thibault

Hello Massimo,
I take advantage of your intervention to congratulate you on the work you are doing, it really is a brilliant tool.
To answer your question, I use a realtek(R) audio card on both PCs.
kenact
Posts: 432
Joined: Thu Apr 23, 2015 6:43 am
Real Name: Ken Coughlin

Based on experiences I had this past weekend, I will be uninstalling the codec package and converting my video files to WMV, so they can take advantage of the built in audio and video codecs native to Windows. I have seen issues with video/audio sync and videos not playing, while using the LAV splitter and codecs provided by K-Lite. I even used a different video player, which used an embedded LAV Splitter, and it had the same problem.

I converted all the MP4 videos from my show this weekend to WMV, removed K-Lite from my system and ran the entire show from home, with no problems at all.
CoS2000
Posts: 105
Joined: Tue Aug 29, 2017 1:00 pm
Real Name:

I had smilar problems when i converted a MP3 file to wav with VLC Player. VLC use the FFmpeg Codec for wav files and QLC had the same problems like here! After that i converted the same MP3 file with audacity and all works fine! I think QLC have problems with FFmpeg! I use audacity only and it works well!
kenact
Posts: 432
Joined: Thu Apr 23, 2015 6:43 am
Real Name: Ken Coughlin

Thank you for providing your workspace but, your project is missing an MP4 video file.

Personally, I have never created a show that includes both audio and video files. I would typically create a single file out of the two. I have also discovered that using LAV splitters can sometimes put audio out of sync.
kenact
Posts: 432
Joined: Thu Apr 23, 2015 6:43 am
Real Name: Ken Coughlin

I think I can finally shed some light on this. I don't believe the audio is the problem. I think the clock/timer in QLC+ is the problem.

I'm on 412.7 GIT and Windows 10 x64

I created a show that is set to run 4m13s962ms. I want a blackout to occur at 4m11s878ms. I placed the Show in a Chase and gave it a Hold of 4m13s962ms. I set up a stop watch and timed the Show. The music plays perfectly, ending at 4m13s962ms, but the lighting cue didn't hit until 4m25s88ms, which is 14 seconds later than it should have gone off, and almost 12 seconds after the how should have ended and gone to the next Step in the Chase. The progress timer starts at the right time, but doesn't finish counting down until 4m25s96ms.

Another weird piece is that I tried to use Audacity to record the audio, thinking the audio was playing to fast, but when I did that, the Show ran fine.

EDIT: I used the Windows stop watch function on the same laptop. The Windows stop watch said 4m13s962ms had passed when the music ended, but the countdown time said there were 12 seconds left.
thibaultphil
Posts: 49
Joined: Wed Nov 04, 2015 10:22 am
Location: Blois - France
Real Name: philippe thibault

thank you for your research. Concretely, what is the solution to put in place. I will test in my environment.
kenact
Posts: 432
Joined: Thu Apr 23, 2015 6:43 am
Real Name: Ken Coughlin

Massimo, you asked a previous poster about their audio driver. Mine is just listed as High Definition Audio Driver.

Previously there was discussion about using video files, so I converted my MP3 to WMV. The timing works as expected, but the obvious problems with this "solution" is that you don't have the ability to look at the wave form to match your lighting to the wave, and a windows pops up when the cue plays.
kenact
Posts: 432
Joined: Thu Apr 23, 2015 6:43 am
Real Name: Ken Coughlin

I'm continuing to test, but there's little consistency to this problem. The exact same project on the same computer will sometimes work perfectly and sometimes not.

What I can tell you is, when it doesn't work, each second takes approximately 1.025 seconds, so the countdown time, and the associated light cues, take 6 seconds longer than the audio file.

I will continue filling in details as I come across them.
Nicow
Posts: 1
Joined: Fri May 05, 2023 7:36 am
Real Name: Nicolas B

Hello to all,

I'm using this topic because I've had the same problem for 2 years now.
When I start the show from the beginning, everything is set correctly, but if I play it in the middle, then the audio will be off.

Example:
There is a drop at 45 seconds in the music, I place a light effect at 45 seconds, if I play from the beginning, everything will be in time, but if I start again at 30 seconds, then the drop will be around 46 seconds

This problem makes it almost impossible to set up Lightshow, since to check each time I have to go back to the beginning.

I have had this problem on 2 computers on Windows.

I'm a developer and I wanted to try to fix this but unfortunately I didn't have the time....
steph19130
Posts: 10
Joined: Sat Feb 04, 2023 6:17 am
Location: France
Real Name:

Good morning?
I am French (google translate)
I also have this lag problem.
I tried almost everything: windows 10, windows 7, ubuntu, convert MP3 to WAV (and vice versa) with several software and codecs, tried several versions of QLC+.
But nothing helps.
Is random ; I start the show I see that it shifts I stop, I go back to the beginning, I play, it shifts, I start again and it's good.
I have an asus R751J (intel core I7, 2.40Ghz)
sound card: realtek
QLC+ version 4.12.7
I do light shows in front of hundreds of people (I'm an amateur), each time I pray before starting the show :) (just kidding).
It's a shame, because I love QLC+. Thanks to Massimo and the contributors for their work.
If anyone could come up with a definitive solution, that would be great.
Thank you so much
Post Reply