Using Audacity 2.0.5 (Oct 2013 build) on Windows 7. I had done something rather uncouth - I came back for the evening church service just in time to start recording, so I hit File->New and started. The morning service was still open, so I closed that window (I’d already normalized it and saved it anyway). I had normalized the track to remove DC offset before putting the computer in “Hibernate”, and I always save before hibernating. So what set Audacity up for the mixup most likely was closing an Audacity window (really shouldn’t have been any file save involved) while recording in another. It was in this project that I closed while recording another where the problem occurred. I’ll find out later whether anything happened in the one I was recording.
What I found later was a block worth of digital silence in the right channel at 41.6 seconds into the recording. I computed the beginning sample number as approx 1834560 (forgot about using the time display mode to do this) and searched the .aup file for a waveblock in that vicinity. There was one, filename=“e0000b30.au” at waveblock start=“1835008”, with rms=“0.0”, which really did contain silence (I played it using SoX). It’s interesting (possibly) that this time value is pretty close to where I was in recording the evening project when I closed the morning project.
After I discovered the problem, I closed Audacity and opened the .aup file in WordPad, which I routinely use to inspect and edit (to rename the project) these files. When I reopened the project in Audacity, there were 2 orphan blockfiles. One contained the same audio as another piece of the project (it had been part of the same Amplify +4.0 operation mentioned below). The other, e0010291.au, contained the missing audio. I edited the .aup file to substitute this filename, which restored the missing audio. I found that one of the changes I’d done at home, Amplify +4dB, had not been done to it so I fixed that. There was no DC offset in this segment, so the file must have been included when I normalized the whole track. That makes sense, since I did that before saving the project and “hibernating” the computer for the afternoon. It does seem odd to me that I didn’t have orphans reported when I first opened the project at home.
The correct and safe way to rename projects is File > Save Project As… then delete the original AUP project file and _data folder.
There is a long standing, almost quashed bug where AU files may get moved between projects. It sounds as if you may have experienced that, but I am sure you won’t be able to reproduce the problem if you did the same again. If you can do so, please write out the steps in logical order 1, 2, 3… and so on.
Note that having project files or folders open in other programs (Explorer, Notepad or so on) is a known trigger for the bug.
In that case, please consider “Rename Project” without re-saving all the data a feature request. Renaming the project to append suffixes identifying what export versions (e.g. CD, podcast, library archive, master for cassettes,…) I’ve provided (via separate label tracks) is my last step in editing every church service. Incidentally, if there’s a place to post batch scripts for using SoX to quickly and easily assemble a variety of Audacity export editions, I’d be happy to share the ones I’ve written. They save a lot of time and avoid the need for multiple versions of audio tracks.
When this happened, Audacity was the only application running. I used WordPad only after I discovered the missing audio, and closed Audacity before launching it. I’m a programmer myself and understand the potential file access and version conflicts that can result from having a file open in more than one program.
It happened again. This time I was not recording when I opened/closed one project while editing another. I didn’t change anything in the project I viewed while editing the other one. I had saved the project I was working on multiple times before I closed Audacity and launched it again the next day. I had an “orphan block file” message, so I let Audacity start up without deleting the block file. I listened to the block file using SoX, recognized where it belonged and found a block of digital silence in its place. Again I fixed the problem by closing Audacity and replacing the file name in the aup file. It’s easy to find the error in the .aup file by searching for ‘rms=0.0"’.
Gale Andrews wrote:
There is a long standing, almost quashed bug where AU files may get moved between projects.
Neither this project nor the one I viewed contains any blocks of entirely digital silence, so I believe the swapped-in block of silence was created by whatever caused the substitution, not taken from the other project. I can confidently say the same of the previous instance. Having multiple projects open simultaneously is not something I routinely do, but considering how long I kept using 2.0.5 Alpha I’m sure I must have done this at least a few times with that version (and older ones) and never experienced this problem. That would have been on Windows XP and Windows Vista, however. Both of these instances are on Windows 7.
As with the previous instance of this problem (the original post), the only change I’d made in the range where the swapped-out block belonged was Amplify, and the blockfile whose name I edited back in had not been amplified. I don’t think there was a block of silence there after the Amplify, so most likely the processed block got deleted. I can’t say whether the Amplify came before or after opening/closing the other project. In the previous instance it came after, since I was still recording the affected one, also the one I closed during recording had been open but saved before I started recording.
Sorry but the developers won’t have patience to read long expanses of closely spaced text with no steps to reproduce. I have no idea of your workflows. Are you saying that the orphan file was not silence, but that you believed it belongs where a silent block file happened to be? Does the problem only happen with Amplify or with other edits?
Note that Amplify or other effects will silence the audio if the block file cannot be accessed. Is your drive working correctly? Is it a network drive?
Are you saying that the substitution-with-silence issue will occur even if you only have one project open?
Again I strongly suggest you should not hand edit AUP files, unless this is a way to make the problem happen so we can reproduce it Renaming the folders the projects are in is much safer.
If you have steps to make the problem happen 1, 2, 3… I’ll be happy to see them, or if you have one or more projects that will reproduce the problem when you reopen them, please post the projects somewhere (close them before zipping them up).