about strange clocks, backups and update

I have at least three questions.
Last night I noticed that at least half a minute of my piece has disappeared. I must have clicked something wrong. Does Audacity make backup files, which would help me to get the lost material back?
Last night also the layout of Audacity changed. If I edit some of the tracks, the others have strange pictures of clocks. Does it mean something? I preferred the older layout without clocks.
I downloaded Audacity 2.2.1 installation file. If I install it, do you recommend uninstalling older Audacity (probably 2.2.0)?
I would like to add about 2 seconds to middle of one track in an empty place. But I don’t want that it makes the later material happen about 2 seconds later. How can I avoid that?
Now I try to attach a picture of the strange clocks:

You’ve accidentally engaged sync-lock by clicking on the clock icon

Uncheck the tick-box I have colored yellow …
Uncheck the yellow box.png

Thank you for your answers. Where is the sync-lock which I had accidentally clicked?


In Audacity 2.2.1 the clock button has been removed (too many people were accidentally enabling it and then getting confused.
“Sync-Lock” is now set in the “Tracks” menu.

Hello again!
I have an Audacity file, which has 12 tracks. Now I want to remove first 1 min 38 seconds. But I want that that the remaining end part remains exactly the same as before, without any changes. Oh no, it’s difficult to explain what I mean. I must draw it.
This is what I want to avoid:
Tracks 1 and 2 before removing stuff:

Tracks 1 and 2 after removing stuff:

Do you know what I mean? How can I avoid that kind of unwanted changes?

The text did not appear as I wanted. I try to explain:
at the middle of the piece something in track 2 begins 2.456 seconds later than track in 1. After removing first 1 min 38 seconds of the file I want that the same thing track 2 still begins 2.456 seconds later than in track 1. How can I make that happen surely?

You can silence the unwanted section you select using “Ctrl” +“L”, that keeps everything in place.

Alternatively, uncheck this box in Audacity preferences …
uncheck the box i have coloured yellow.png
create boundaries , then delete the unwanted section, (rather than silencing it).

I have a new question, which is opposite of the previous one. If I want to add 10 seconds of silence to the beginning of the file which has many tracks, how can I do it? Of course one possibility is making a new file and copying everything from the old file beginning 10 seconds later, but I believe there must be a simpler solution.

Select all the tracks, (press “Ctrl” +“A”), then move the cursor to the start, (press “J”), then generate silence, which will be added to the start of all the tracks …

Last night I tried to remove 90 seconds from the beginning of my Audacity file, which has many tracks. Those 90 seconds are total silence (there used to be sounds before). I want that 01:30:000 becomes 00:00:000. How do I do it? I have done it many times to a single track, but it seems to be different when there are many tracks.

One way is to drag the cursor across the tracks …
drag cursor across the tracks, then delete.gif

P.S. It seems that this question is not yet seen on the website:
I want that 1:30 (90 min) becomes 0:00 - I mean that the first 90 min disappear totally from the aup-file which has many tracks. I did not succeed to do it? Do you know how it’s done? I have done it many times to one-track files.

P.S. Now I see the answer. Thank you for your help.