blank uploaded songs

I have read that certain encoders don't play nice with iTunes Match which is probably what is causing the issue you're having. Do you have the original files you encoded with Audacity in Lossless that you could then transcode in iTunes? There won't be much point in transcoding the existing AAC files since all that will do is degrade the quality.

Suggestion to help troubleshoot: extending on what Michael wrote, there could be a few things going on.

- Download this tool: http://mediainfo.sourceforge.net/en. It's free, it's cross-platform and I find it very important for my own troubleshooting.

- Open up the original file test file with that tool, go to view \ text and keep it open.

- Upload the test file, verify it's failing to play on another iTunes iTM system.

- Download the uploaded iCloud file, open that up in the mediainfo tool as well (view \ text) and compare them.

What we're looking for is to see if they are the same. Specifically the "Writing Application". Now I just did this myself with an Audacity encoded AAC, and it's showing as "Lavf32.64.2" on both my files (no issues playing it on a second iTM iTunes system btw). But this tells me that Apple isn't altering the actual encoded file in my case, although it does add some extra metadata text like your Apple ID.

But, if the Writing Application has changed to "iTunes 10.5.2", then that means that iTunes didn't like the original encode and transcoded it before upload. And if that happened to you, maybe something went wrong with the transcode where it's causing some type of corruption.

EDIT: You shouldn't have to pay for an incident, btw - just call the main Apple number and ask for iCloud support - there are L1 reps that will help you with iTM. I call them almost weekly. 🙂 However, you'd probably need an L2 rep for this issue, at the very least.

Sorry if you weren't able to find the thread where I discussed this, but I went through exactly this situation a month back with Audacity created AAC files uploaded to iTunes Match. I determined there is some difference in encoding done with certain lame flavors. I decided that while iTunes Match is allowing these files to upload, they really should be flagged as ineligible.

While I now export from Audacity using AIFF and convert to AAC in iTunes, the fix for my problem files was simply to create another AAC version within iTunes and swap them for the files in the cloud. Every new AAC plays fine. It was a bit of a pain to identify every album where I had these issues, but one thing I decided to do that helped me a bit was to just convert the entire album instead of separating matched files from uploaded ones.

If you're not familiar with how to swap files in the cloud, there are several threads where it's been detailed.

p.s. the original files played fine in iTunes. I believe the problem has to do with how playback is handled in the cloud. I did not, however ever download the troublesome tracks, so I've not experienced exactly the situaiton the OP has. My guess is I would have had the same problem though.

I found the original posting I did on this subject.

https://discussions.apple.com/thread/3567775

Glad it worked for you, though I'm a bit puzzled that you didn't find under the Advanced menu "Create AAC Version". That's what I used.

Glad you got it worked out.

gardnern wrote:

You are correct, as is Jimin's comment concerning the encoding of the files. It is frustrating that Apple would allow such to go through.

I could be wrong, but I don't think this is a matter of Apple allowing "such to go through," but more a matter of Audacity using an ecoder that is non-standard. iTunes and iDevices are pretty robust in their playback support, but they are limited. And obviously the iDevices don't like every MP3 encoder out there.

Audacity is using FFMPEG as its backend. This is a fairly standard open-source tool for encoding, and probably the only one available to it for use as a free tool. I'm not 100% sure of this, but AAC might have been reversed engineered to be used with FFMPEG.

That being said, I personally wouldn't use it to encode AAC's, just for the reasons already stated. I've personally been using Netro Encoder (bundled with Audiocoder) for my AAC-based CD rips (as well as vinyl "on the go" lossy files) and haven't had any issues with iTM imports yet. But then again I didn't have any issues with the Audacity AAC files I created as tests either.

Keep in mind that AAC is not an Apple format, believe it or not. It's actually an ISO standard, created to replace MP3. And, like MP3, it's not open source - you do need to pay royalites for encoding (and thus the concerns with FFMPEG).