No audio on playback

I have a macOS Sierra Version 10.12.6. I’m using Audacity 2.3.2. So I recorded from a tape deck through an audio interface through Audacity. I followed the instructions for setting the volume level from the input, setting a peak at about -6DB.

I hit “Record” on Audacity and then started the tape player, recording for about two minutes.

I played back the recording but could only hear a very faint audio, even with the computer’s speakers turned all the way up. The playback volume on Audacity was maxed out as well. The playback meter on Audacity indicated the audio reaching -6DB.

Any suggestions as to what went wrong?

Also, when I created a new Project for the file, I got a message stating that an Audacity project could not be used in other apps. The message said to use “export” instead, but this function was “grayed out” and unavailable. Is it proper to save as an Audacity project?

Thanks for any assistance.

I’m now getting audio on playback, problem resolved. Don’t know if this will help Samboo, but I called up Apple and they directed me to System Preferences, then I clicked on Sound, and on the Input screen we verified that the internal microphone was working.

After this, for some reason I got audio on the same Audacity track that was soundless yesterday.

I am still not able to get any audio while I’m recording, whether I select “Built In Output” or my audio interface on the “Playback Device” bar. Any suggestions as to how to resolve this?

Thanks for any response.