P: .MTS video and audio not synched on Mac OS and Adobe 24

Today I went from PP 24.6.3 to PP 25.2.3. The out-of-sync problem in m2ts files is obviousely gone. Perfect!

March 11, 2025

I think I found a temporary solution. I have no idea how but it works for some reason

First open media encoder -> add the clip in queue -> click play. (The output file is in mp4 and it does not have audio)

Create a new premiere file -> add the MTS clip (not the mp4 file you just got from media encoder) and your audio should now be synced.

Then export.

You must create a new premiere file for each clip with the delayed audio. 

ONLY import ONE clip at a time.

Hola, tenemos un problema en la universidad en la que trabajo, desde la versión 2024 hemos venido teniendo problemas con Premiere, pero con la versión 2025 es más común, en varias salas está instalado Adobe Premiere Pro versión 2025 y los estudiantes al editar, después de uno minutos se les desfasa el audio con el video, y no vuelve a cuadrarse hasta que cierran el programa y reinician el equipo, esto le sucede a más de 20 computadoras, ellos trabajan con video en .MTS y .MP4 y con los dos sucede lo mismo. 

¿Qué se debe hacer en ese caso?

Just adding to the conversation. I am having the same issue with M2TS files. I assume it is because that's an AVCHD format as well. With 25.1 just having been released, any idea when 25.2 will release from beta? I can't believe it has taken Adobe this long to issue a fix.

I'm having a problem with M2TS files being out of sync by 16 frames. This only happens in Premiere Pro. 

It started with an update this past summer. I was hoping the update that just came out this week would finally include a fix. 

I have to adjust every M2TS clip. What's weird it only happens with new projects. If I import an old project with M2TS files the audio is in sync. If I import MOV from an iPhone or MP4 from my Galaxy phone into a new project it's fine. 

I see lots of other threads with people having issues with sync issues and in one of them, Adobe said a fix was coming soon. That was in November. Is there any fix for this or workaround so I don't have to adjust my clips? 

When will be a fix for <https://community.adobe.com/t5/premiere-pro-discussions/issues-with-premier-pro-not-syncing-audio-and-video/m-p/15112289#M550300> available? 
I have quite similar issue: 
First, new imported *.MTS-audio wasn't played in Adobe Premire Pro (v25.0.0, Build 61) due to AC-3 is not supported in Win11 24H2 anymore. 
Installing AC-3 manually (<https://www.majorgeeks.com/files/details/dolby_ac_3ac_4_installer.html>) brings audio back in Premiere Pro (v25.0.0, Build 61 and v25.1.0, Build 73) but reproducible out of lip-sync. 

Operating system: Windows 24H2 
CPU: AMD Ryzen 7 1700 Eight-Core Processor, 3.00 GHz 
GPU: NVIDIA GeForce GTX 1050 Ti 
HD/SSD: Western Digital Blue SN570 2 TByte NVMe SSD 
RAM: 16 GByte 

Camera (not a smartphone): Sony HDR-GW66 
*.MTS-File info: 

General
ID : 0 (0x0)
Vollständiger Name : C:\Eigene_Dateien\import\07.02.2025_Matthias_Rackwitz_und_Jana_Schimke_in_KW\20250207114016.m2ts
Format : BDAV
Format/Info : Blu-ray Video
Dateigröße : 1.94 GiB
Dauer : 10 min 27 s
Modus der Gesamtbitrate : Variable
Gesamte Bitrate : 26.6 Mb/s
maximale Gesamtbitrate : 28.0 Mb/s
Bildwiederholungsrate : 50.000 FPS
Aufnahmedatum : 2025-02-07 11:40:16+01:00
Kodierendes Programm : Sony HDR-GW66VE

Video
ID : 4113 (0x1011)
Menü-ID : 1 (0x1)
Format : AVC
Format/Info : Advanced Video Codec
Format-Profil : High@L4.2
Format-Einstellungen : CABAC / 2 Ref Frames
Format-Einstellungen für CABAC : Yes
Format-Einstellungen für RefFrames : 2 frames
Format settings, GOP : M=1, N=12
Format settings, Slice count : 4 slices per frame
Codec-ID : 27
Dauer : 10 min 27 s
Bitraten-Modus : Variable
Bitrate : 25.3 Mb/s
maximale Bitrate : 26.0 Mb/s
Breite : 1 920 pixels
Höhe : 1 080 pixels
Bildseitenverhältnis : 16:9
Bildwiederholungsrate : 50.000 FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scantyp : Progressive
Bits/(Pixel*Frame) : 0.244
Stream-Größe : 1.85 GiB (95%)
IrisFNumber : 3.400000

Audio
ID : 4352 (0x1100)
Menü-ID : 1 (0x1)
Format : AC-3
Format/Info : Audio Coding 3
Commercial name : Dolby Digital
Codec-ID : 129
Dauer : 10 min 27 s
Bitraten-Modus : Constant
Bitrate : 256 kb/s
Kanäle : 2 channels
Channel layout : L R
Samplingrate : 48.0 kHz
Bildwiederholungsrate : 31.250 FPS (1536 SPF)
Compression mode : Lossy
Stream-Größe : 19.2 MiB (1%)
Service kind : Complete Main
Dialog Normalization : -31 dB
compr : -0.28 dB
dialnorm_Average : -31 dB
dialnorm_Minimum : -31 dB
dialnorm_Maximum : -31 dB

Text
ID : 4608 (0x1200)
Menü-ID : 1 (0x1)
Format : PGS
Codec-ID : 144
Dauer : 10 min 27 s

Regards, Andreas

bonjour, lorsque j'importe mes rushes .mts (issues d'une Canon EOS C100 mkII) le son est désynchronisé et je n'arrive pas à trouver la solution .

Merci pour votre aide

Another thought I had was that, as Kevin et. al. have pointed out, the native format of the source material (AVCHD) is not a good format at this time.  He has suggested transcoding the source to ProRes LT (I don't know where to start to do that) before importing it.  There are several AVCHD settings available for Editing Mode under Sequence  and here are mine.  I note the Editing Mode in mine is "Custom".

The source file information is in a post on Dec 30th.  I thought I had read somewhere that the sequence settings were auto  adjusted to the first input file's settings, but I'm probably wrong about that.  What do you suppose would be a good selection to use for these files from the dropdown?  I don't know enough about AVCHD to be able to intelligenly select an option.  I can barely spell it!

In general, going to the beta version seems to have fixed the major destruction of the audio in my first clip.  The other clips seem to have also survived the import process.  I have not tried to export the raw, full sequence yet, perhaps I should.  Any suggestions for a suitable output.  This is a perforomance archive, only the actors AND ME, will be annoyed if it is a "little" out of sync.

Thanks, Mitch_98 and Averdahl. I located the Beta, installed it, and imported the troublesome clip into a new project.  It survived!  I was able to render both audio and video.  So I imported the other two clips and set them to render in to out.  I got the following error:

I don't know exactly what any of it means, but the three files in my project timeline end at 1:1:42:39 -- I don't know why it's working in the stated timecodes.  Ideas?