Choice of Audio Driver is an issue when using MIDI softsynth and the MIDI part is lagging due to latency.

The Options-Preferences->Audio section is where to handle this issue.

If you have ASIO sound drivers available, use those instead and the Latency figure will be then handled by the sound device drivers and control panel and not by RealBand.

If using MME Windows Sound drivers, try hitting the "Default (MME Drivers only)" wizard button that forces an automatic Wizard to analyze your sound card and come up with settings that should work.

More info from you as to what MIDI softsynth you are trying to use at the time can shed more light on the subject if the above doesn't do the trick for you.

--Mac