Musical Mode = heavy, awful crushed distortion

I have imported audio tracks from another cubase session and those that are in musical mode create this awful, distorted sound which disappears when musical mode is turned off. I have tried bouncing while they are in musical mode but this includes this horrible distortion. Any ideas please?

Cubase 10.5.20


Is the tempo shown for the file(s) in the pool correct for when the audio was recorded? Does this occur if the Pool & Project Tempos are the same? What Algorithm are you using and have you tried any others? Is it trying to change the tempo by a large amount? Any other info that might be useful?