Mixdown Volume Lower than original

Hi guys,
I’m on Cubase 10, last update.

Yesterday I’ve found out a strange thing.
I’m on a very easy recording project (drums over a backing track). I do all the recordings and editing than I choose to mixdown tracks.
When I re-import those tracks in the same project I get a smaller waveform and obviously lower volume.
I tried to mixdown both in Stereo Out (exporting mono) and in Multi-Channel option.

No plugins in insert, nothing on the stereo out, nothing used in the cubase channel strip. Only a couple of 180 phase flips in the “pre” section" of the cubase rack.

Any idea?

What is the level of your stereo output faders at the time of the mixdown?

Well probably a couple too many then.

What problem are you trying to resolve by changing the phase?

I’ve been recording audio for… lets just call it a really long time. Over that time I’ve probably changed the phase 3-5 times total, and never multiple times in a single Project.

0 dB. All at 0 dB.

Don’t know why you don’t change the phase but actually I do many times. And I’ve been recording audio for a really long time, too.

This time was to phase align left and right overheads with kick and snare.

Anyway in a blank project the problem is absent.
Don’t understanding why in that project I still have that behaviour…

Maybe posting a screenshot of your audio mixdown window settings and/or the mixer channels would help. Are any of your channels set to ‘Monitor’ active at the time of the export?