Hi,
Are you aware of the Set Tempo From Event feature, please?
- Import Audio file to a project.
- Select the Audio Event.
- Make sure the Musical Mode is disabled on the Audio Event.
- By the Left-Right Locators, set the wanted number of bars.
- Audio > Advanced > Set Tempo From Event
=> The tempo is set so the Audio Event fits to the bars, you defined.
Before:
After:

