MP3 Export file too short

Having just upgraded from Cubase Studio 5 to Cubase Artist 9.5, I’m experiencing a strange issue.

When exporting audio to MP3 (in either real-time or not), the resulting file is too short. For example - the track is 2:50, yet the resulting MP3 is only 0:57. The locators are set correctly, as I can see the real-time export as it’s happening.

To investigate, I chose “import to pool” on export, and sure enough the resulting WAV converted file was the correct length. So then, I created a new project, imported the WAV version and exported to MP3 successfully.

But going back to the original project, and trying to export straight to MP3 it’s doing the same weird thing of coming out with a very truncated file.

I’d be very grateful for any ideas as to what’s going on here…

A related bug - when you export a longer song to mp3 in one project and then a shorter one in another project, it adds the end of the longer one to the shorter one. Oops!!