Good advice to try from Noel.

I'm puzzled by this.

You should always try Opt., Return to Factory Settings when things don't work as you think they should. You will first be prompted to save your settings, so it's safe.

Did you by any chance use the Audio Chord Wizard and create a tempo map? I know you said there were no programmed tempo changes, but that is different.

And, when you say all the other tracks did not slow down, only the RealDrums track, were those other tracks MIDI or RealTracks? I don't know what to do based on the answer to this, but it might help diagnose the problem.

Since you have a new PC, it's unlikely that this would help, but there are some settings in the Preferences, RealTracks and RealDrums dialogs that can improve their performance. Hover over the checkboxes for explanations.

You might want to give PG Music Support a call on this one if none of the above ideas are on target.

BIAB 2025 Win Audiophile. Software: Studio One 7 Pro, Swam horns, Acoustica-7, Notion 6, Song Master Pro, Win 11 Home. Hardware: Intel i9, 32 Gb; Roland Integra-7, Presonus 192 & Faderport 8, Royer 121, Adam Sub8 & Neumann 120 monitors.