Tsunami2 Independent Train Brake. . . F11. . . Engine Continues to Rev?

I enabled the Independent Train Brake function (F11) on my Sountraxx Tsunami2 decoder. I changed CV 1.403 to 0 and updated CV 117 to 10. The braking works properly. . . when F11 is pressed, the brake sound comes on and the engine comes to a complete stop. However, when the engine is stopped, the motor continues to rev to "notch 8". When I release the brake (press F11 again), the brake release sound comes on, the loco moves forward and the engine revs down to "notch 1".
How do I get the engine to stop revving when the loco is braked/stopped?

[@thomasboese3793]

Prototypically after the independent train brake is used there would be a time lag to rebuild airline pressure. (The engineer may leave the notch setting or notch up based on need.) Is the software accounting for the need to restore the air line pressure? Or are the various functions totally separate?
I would try to talk to someone from Tsunami and find out what their design parameters are.

[@westernstatesrailroading]

Thanks. . . I did receive a reply from Soundtraxx and this is the normal behavior. I just need to notch back the throttle when the loco is braked. From there, it seems to work without notching up all the way.

[@paulatkinson7722]

The "lag" in response to the brake command is due to hysteresis in the system