distorted audio PCM track

[dabelstein]

Hi
I have a few DVDs that when ripped end up with distorted audio. The tracks are always PCM 16bit, 2 channel, 48 khz, 1536kbs. They are all commercially released DVDs of music clips or concerts.

Strange that when the DVDs themselves are played there is no problem. It is only when the MKV is played.

Does anyone know what might be happening or what I can do to troubleshoot this??
regards

Greg

[Woodstock]

What profile are you using?

Generally speaking, MakeMKV does not change audio tracks, unless you ask it to. The FLAC profile is one that will do conversions. I do remember a few requests to convert 16-bit to 24-bit LPCM, but Mike rejected them as throwing lots of zero bits at a non-problem, since there was no advantage. The history notes have nothing LPCM-related since v1.9.2.

One publisher I get a lot of stuff from uses 24-bit LPCM as their primary audio codec, and I have not heard the distortion on those disks. I'd have to look to see what I have with 16-bit.

[dabelstein]

Hi Woodstock

Thanks for the reply. I appreciate you taking the time to help.

I'm just using the default profile.... I've also noticed that when I play one of the troublesome discs in VLC the audio codec is DVD LPCM....but when i play the same disk as an mkv it is araw...not sure if that has something to do with it.

I also notice that the disks have a lot of "AV sync issues in stream 1 at xxxxx with duration of 1.666ms - audio gap filled with silence"...so many that they end up only being printed to the log file.

regards

greg

[Woodstock]

If MakeMKV is trying to synchronize the audio and video, the silence gaps would be rather noticeable when they get that frequent.

I'd suggest sending the information requested in the FAQ link in my signature to support@makemkv.com for Mike to look at. There might be a different way to keep the audio in sync when the time stamps are that out of wack.

[turnkit]

I'm having this same trouble. I am getting repeated "fill gaps with silence" messages too.

Is there any fix for this? VLC plays the discs directly fine, but VLC plays the mkv rips with terrible stutter sounds on most of the music video titles on this disc. Some work okay but most are bad.

AV sync issue in stream 1 at 0:00:00.040 with duration of 1.666ms : audio gap was filled with silence
AV sync issue in stream 1 at 0:00:00.081 with duration of 1.666ms : audio gap was filled with silence
AV sync issue in stream 1 at 0:00:00.113 with duration of 1.666ms : audio gap was filled with silence
AV sync issue in stream 1 at 0:00:00.155 with duration of 1.666ms : audio gap was filled with silence
AV sync issue in stream 1 at 0:00:00.196 with duration of 1.666ms : audio gap was filled with silence
AV sync issue in stream 1 at 0:00:00.228 with duration of 1.666ms : audio gap was filled with silence
AV sync issue in stream 1 at 0:00:00.270 with duration of 1.666ms : audio gap was filled with silence
AV sync issue in stream 1 at 0:00:00.343 with duration of 1.666ms : audio gap was filled with silence
AV sync issue in stream 1 at 0:00:00.385 with duration of 1.666ms : audio gap was filled with silence
AV sync issue in stream 1 at 0:00:00.416 with duration of 1.666ms : audio gap was filled with silence
AV sync issue in stream 1 at 0:00:00.458 with duration of 1.666ms : audio gap was filled with silence
AV sync issue in stream 1 at 0:00:00.500 with duration of 1.666ms : audio gap was filled with silence
AV sync issue in stream 1 at 0:00:00.531 with duration of 1.666ms : audio gap was filled with silence
AV sync issue in stream 1 at 0:00:00.573 with duration of 1.666ms : audio gap was filled with silence
AV sync issue in stream 1 at 0:00:00.615 with duration of 1.666ms : audio gap was filled with silence
AV sync issue in stream 1 at 0:00:00.646 with duration of 1.666ms : audio gap was filled with silence
AV sync issue in stream 1 at 0:00:00.688 with duration of 1.666ms : audio gap was filled with silence
AV sync issue in stream 1 at 0:00:00.761 with duration of 1.666ms : audio gap was filled with silence
AV sync issue in stream 1 at 0:00:00.803 with duration of 1.666ms : audio gap was filled with silence
etc...

[Woodstock]

The path to a fix is the same as before - provide information to the program's author, per the FAQ link in my signature. It's hard to fix something if you cannot reproduce the problem.