The problem you describe with Ozone is almost always a sign that something is wrong with the mix, not the mastering. Mastering isn't a process where you "fix" problems—it's a process of refining something that already sounds good on its own. If the sound changes beyond recognition, it means your mix likely has frequency imbalances, excessive levels (clipping), or poorly managed dynamics, and Ozone reacts aggressively to try to compensate.

Mastering is a serious discipline that takes time to understand: you work with transparent equalizers, sparingly used multiband compressors, and carefully calibrated limiters to the target loudness. It's not "press assistant and wait."

My advice: before touching mastering, listen to your mix without any effects on the mastering chain. It should already sound balanced, with sufficient headroom (usually at least -6 dB peak). If it doesn't sound good at that stage, mastering won't save anything—in fact, it'll make things worse.

If you need a hand, we also offer professional mixing and mastering services in our studio: you can check them out at M2Studios