The delay in the ability to copy multiple music tracks from one project and paste to a new project

rhorowitz32 · October 21, 2026, 5:32pm

Copy and Paste - Not responding .. Ihave a 14 track music recording of several songs. I wish to copy one song with all 14 tracks and open a new project to enable me to mix/master the song. The song I copied is 5 minutes long and it takes a very long time generate the new project after a paste and slways reads “not responding” in the header. It finally renders after a minute or two of spinning

billw58 · October 21, 2026, 7:04pm

To be clear, you have a project with 14 tracks and several songs one after another on those tracks? You make a selection across the 14 tracks, Copy, then Paste into a new project.
If this is the case, what is happening is Audacity is actually bringing all the audio on all 14 tracks into the new project, but just displaying the sections you selected when you copied the audio.
This is because of “smart clips”.
I’ve raised an issue on Github to have this addressed.

github.com/audacity/audacity

AU4 is missing AU3 preference for pasting audio between projects

opened 07:05PM - 25 Sep 26 UTC

billw58

bug

### Bug description Audacity 3 has a preference at _Tracks > Track Behaviours >… Pasted Audio_ to specify what happens when audio is pasted between projects. Option 1 is that the pasted audio includes the entire clip the selection was in. Option 2 is to include only the audio in the selection. There is a third option to ask each time. Audacity 4 does not have a preference and always uses option 1. This can result is enormous projects with certain workflows. See https://forum.audacityteam.org/t/how-can-i-trim-my-clips-to-no-longer-have-hidden-audio-in-audacity-4/154293 ### Steps to reproduce 1. Open or create a project with a single, long clip, say 45 - 60 minutes. 2. Open a second project. 3. Paste multiple different selections from project 1 into a project 2. Note delay with each paste. 4. Save both projects 5. Compare sizes on disk. ### Expected behavior Should Audacity be smart enough to know that all these pieces of pasted audio come from the same source clip and copy in the audio once, then make pointers to it? Or should it be simple and let the user decide? ### Actual behavior Each smart clip brings the entire audio from Project 1. ### Audacity Version Audacity 4.0.0 ### Operating system OS independent ### Additional context I did an experiment. Project 1: One stereo clip 44 minutes long, 44.1 kHz, 32-bit float. 949 MB on disk. Project 2: 8 different audio selections pasted from Project 1, 44.1 kHz, 32-bit float. 8.54 GB on disk. Surely we don't want this to happen?

There is no way around this in Audacity 4.
If you want to get around both the delay and the presence of the audio of all the other songs in the second project, you’ll need to migrate your project to Audacity 3. If you want to do that let me know.
See this post for a similar report: