Sound on one deck drops out. Warning [CachingReaderWorker 2]: SSFLAC: Seeking error at file (...)

[Andreas Groschang]

Mixxx 2.0 RC2 on Ubuntu Studio 14.4

Today when broadcasting via icecast the sound on deck 2 suddenly dropped out. UI showed the track playing on, but no sound.

When i re-loaded the track into the same Deck it wouldn't play at all, just a short clicking sound when i pressed the play button. I had to restart mixxx to get it working again.

In the log it says "Warning [CachingReaderWorker 2]: SSFLAC: Seeking error at file (...) over and over.

I haven't been able to reproduce this behavior so far.

Would it help providing you with the flac file in question?

[Daniel Schürmann (daschuer)]

By luck, the issue is solved in current master.
Please try http://downloads.mixxx.org/builds/master/debug/
And report here.
Thank you.

[Andreas Groschang (kontpkt)]

Awesome, thanx a bunch.
I'll let you know if i run into this problem again.

[Uwe Klotz (uklotzde-deactivatedaccount)]

Seems to be a duplicate of a bug that has already been fixed on master:

https://bugs.launchpad.net/mixxx/+bug/1422114

Well, not really fixed, we just implemented a workaround. Please consider re-encoding the affected files with FLAC 1.3.1, because only this will fix the file itself.

And also please have a look at the linked forum threads for related discussions.

[Uwe Klotz (uklotzde-deactivatedaccount)]

If the issue is not fix in 2.1 alpha (as I expect) an example file would be helpful for further analysis.

[Andreas Groschang (kontpkt)]

Yup, just as you suspected, i transcoded all flac files with a way outdated flac version 1.2.1, never gave it much thaught before. So there were a lot of chances for things to break. ;-)

I'll hold on to my broken flac files and try the alpha asap, however it took me 2 hours to run into the problem for the first time and i've been using 1.2.0 beta for months before without any issues. So i can't guarantee i'll be able to reproduce the bug again.

Is there an easy way to revert to version 2.0 after testing the alpha? Because for the time being i'm not feeling comfortable using an alpha version for anything beyond testing. For real life usage i'd rather stick with v. 2.0 and transcode my files as you suggested.

[Andreas Groschang (kontpkt)]

Here's the file that failed to play.

[Uwe Klotz (uklotzde-deactivatedaccount)]

There is no easy way back from the alpha, because the schema of the database has been modified. Please test 2.1 with a copy of your library or a new library.

I would recommend transcoding your affected files using FLAC 1.3.1. This latest version was able to repair all "flaky" FLAC files reliably. Unfortunately we didn't find any evidence in the FLAC change log of a bug fix related to those issues.

[RJ Skerry-Ryan (rryan)]

It's true the schema is modified in 2.1 alpha but it's backwards compatible all the way back to Mixxx 1.9 since all it did was add a column -- so it's safe to try 2.1 alpha and then downgrade to 2.0.

[Andreas Groschang (kontpkt)]

The fix looks good so far.
I played the cursed file on repeat in all 4 player decks and all sampler decks with different loop points.
While this made version 2.0.1 fail within the first minutes, 2.1 alpha is playing the file nicely for about an hour now without any problems.

[Andreas Groschang (kontpkt)]

I ran into the same problem again, this time with a libflac 1.3.1 encoded file that reliably makes mixxx fail.
Looks like "flaky FLACs" are still an issue after all.
I'd suggest warning the community of using flac files for the time being, until a release containing the fix/workaround for this problem is out.

[Swiftb0y (swiftb0y)]

Mixxx now uses GitHub for bug tracking. This bug has been migrated to:
https://github.com/mixxxdj/mixxx/issues/8389