Stereo Out Clipping when master is not

Hi, I’m having a weird issue. Everything in my session is routed to a group track called “Master” which is then routed to Stereo Out. This is the only track routed to Stereo Out. I have an instance of Ozone 9 (for the limiter) on my Master track and activated “true peak” so it doesn’t go above 0 dB. The master track itself doesn’t go beyond 0 dB, but the Stereo Out track goes to 1-2 dB… I don’t have any effect or plugin on the Stereo Out track…

Do you have an idea of the cause?

Thanks!