No sound in Cubase on tracks with volume automation

This is a strange one indeed, got one project from 8.3 and the only sound I can get out of it in 8.5 is if I click the listen button on any track! Main issue is its stopped the project playing back in 8.3! Fortunately it’s just a scratch pad that’s being built up but that’s not the point, gonna have to take a closer look and trash the preferences that were bought over from 8.3…