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superbad
2007-05-18, 20:03
I got a new SB3 a couple weeks ago, after several years of SB1 use. Now I am finding that some of my Apple Lossless songs turn into garbled static after a while (sometimes a few hours, sometimes a few seconds). They sound like they are being played underwater- you can still recognize the song, it's just messed up. Forum and bug search turned up nothing. My only thought is that it could be some kind of alac problem. Any ideas?

This is on OS X, using the 6.5.2 build from 5/18. It was set to transcode to wav, tried switching to flac, same thing. No bitrate limiting being used.

squeezephil
2008-03-10, 17:12
I'm running Mac OS X 10.4.11 with Quicktime 7.4.1 and am managing my music with iTunes (Lossless & AAC). About every third Apple Lossless file will play total static noise and crash alac. This happens both with SlimServer 6.5.x and the official SqueezeCenter 7.0. All files play just fine in iTunes. My SqueezeBox is connected wireless via a Linksys WRT54GL 54MBit Wireless Router to our internal/external network managed by a Linux server.
The SqueezeBox plays FLAC, AAC and MP3 files without any problems.

I can't find any logic why certain lossless files play and others do not, although it seems to happen more frequently with older Apple lossless files (converted in 2007).

I had this problem since the beginning of my SqueezeBox 3 purchase last autumn 07 and reported it as bug to SlimDevices. Thereafter, I converted everything to FLAC and even though this did not produce any playback problems, I have now switched back to AL again due to the significant song management overhead and wasted disk space (Lossless & AAC & FLAC).

I don't quite understand why SlimDevices is claiming Apple Lossless compatibility without ensuring a stable functionality or at least offering solutions to this problem. On the other hand, maybe the majority of Apples Lossless users are not experiencing any problems, but then why do we few? Or is it the reason that most SqueezeBox users are on PC/Linux platforms and do not care about Apple Lossless?

Any helpful suggestions as to possible causes/solutions GREATLY appreciated - thanks!

Update: OK, I checked my old bug report in the repository and, thanks to the answers by the developer team, remembered the reason again why certain Apple Lossless files will crash alac! 16bit encoded files will play fine but not 24bit files! While the support team stated back in November 2007 that they would contact the author of the open source library alac if he could fix this bug, nothing has happened at all since then. alac was last updated by the author in mid 2006, an he does not appear to be very keen in maintaining it!

The question now is as to why SlimDevices/Logitech are not taking their (over)due responsibility over alac, or write their own codec library for this important functionality promised in the SqueezeBox marketing literature? Not that I would hesitate to convert all my 24bit Apple Lossless files to 16bit, but how? iTunes does not provide a relevant option.

Nothing against open source, dear SlimDevices, but such core commercial product functionality problems are just not up to professional levels.

Josh Coalson
2008-03-12, 21:53
apple does not license apple lossless, every non-apple device has to rely on the reverse engineered decoder which has limitations.

reverse engineering the format is actually quite a lot of work, and apple can break it any time by tweaking the format. that's what you buy into when you use a proprietary codec; it's only smooth if you accept apple lock-in.

Enoch Soames
2008-03-13, 08:22
Way to go, guys. I've got nearly 500gb worth of Apple Lossless files (all of which play fine) but now I'm paranoid.

Can someone explain the difference between 16 and 24-bit Apple lossless files? It doesn't appear to be a user-selectable choice (in iTunes, anyway, which is what I'm using.)

bigfool1956
2008-03-13, 08:32
You will only get 24 bit ALAC files if your original source was a 24 bit file.

In other words, if all your files were ripped from CD, then you will have no 24 bit files.

Note: iTunes cannot convert the bit depth from 16 bit to 24 bit, or vice versa. You can however feed it 16 or 24 bit files, with 44.1, 48, 96 sample rates and it will happily pack them into ALAC. (It may do other sample rates and bit depths, these are the ones I have tried)

Enoch Soames
2008-03-13, 08:45
Got it. Thanks for the quick answer.

squeezephil
2008-03-13, 08:50
Neither am I happy with Apple's tedious proprietary games, to say the least. But I'm a Mac user and it just happens that iTunes is great and easy music management application also offering high-quality audio codecs.

But there is no doubt that Logitech has the resources to support some further development of alac. Some financial incentives would surely provide alac's author the needed motivation to polish this fine piece of software ;)

Btw, I converted all my 24bit files to 16bit with the newly purchased Amadeus Pro, which was the only software capable of 1. processing Apple Lossless 24/16bit, 2. batch converting & replacing them in place in iTunes' music folder, 3. retaining all meta tags, and 4. doing it fast.

Josh Coalson
2008-03-13, 11:33
Neither am I happy with Apple's tedious proprietary games, to say the least. But I'm a Mac user and it just happens that iTunes is great and easy music management application also offering high-quality audio codecs.

But there is no doubt that Logitech has the resources to support some further development of alac. Some financial incentives would surely provide alac's author the needed motivation to polish this fine piece of software ;)
they could do all that, and apple could break it all in one itunes update, and you'd be back to square one.

apple is really the one to appeal to here, to open it up, or better for everyone (including apple), support flac:
http://flac.sourceforge.net/itunes.html