How do I reduce the volume of the metronome on a Yamaha E423 keyboard?

Question

I am using a metronome to get grip on my best timings. Currently its volume is too high, so I want to reduce it. What is the setting for it?

Note: I do not want to reduce the volume of my keyboard music. I only want to reduce the volume of metronome.

I have tried M.Volume settings under Category. But when I turn the wheel, the volume is not reducing.

Answer 1

I found the answer.

It was MtrVol function.

It was not M.Volume.