please help audio sync issues

Hi I hope someone can help, this is driving me nuts
I have scored a short fighting film clip with lot of foley that needs to be tightly synced in cubase 10.i export the original foley and music from cubase as one audio file and drag into FCP from finder. when I line up the new audio at the start of the video it is out of sync by a second almost like the audio export has added some silence to the start. The wav peaks of the imported foley/music do not line up with the original foley that FCP imports as part of the video. even if I extract the original audio that cubase extracted and put it into final cut pro its out of sync. I've checked the fcp and cubase project frame rate are the same 23.98, 48k. tried exporting as wav.aiff, 16bit, 24bit,32bit. both 48k. just can not see why it would be out of sync.

thanks for any suggestions I hope my question makes sense

Bit depth has zero to do with your issue. Normally if it drifts out of sync over time, that would be a sample rate issue. DAWs unfortunately introduce frame rate issues, also.

So the only issue you have is the audio you import starts a second too late? Trim it, be done.

I'd open the audio you exported from FXCPX originally into QuickTime player and see if the one second delay at the beginning is there.

What is the total duration of your Project in FCPX to start with?
What is the total duration of the clip (is it video/audio or just audio) you export from FCPX?
What is the total duration of the clip you export from Cubase?

And just out of curiosity, why not do the foley work inside of FCPX?