[ midi-expert needed ] Keyboard Got No MIDI sound

Having trouble with LMMS? Ask about it here.
I have an old NI Keyrig 49 USB connected to my computer which is running LMMS on WinXP

LMMS shows me MPU-401 and USB Audio Device as connected MIDI devices.

But get no sound nor any indication on the screen of any activity when I try to use he keyboard regardless of which of these choices I use.

I followed the instructions on the LMMS site. Seemed simple enough. But no result.

I went into settings/MIDI and it has WinMM Midi selected.

Any ideas what I should try next?
On what synth are you trying the midi input ?

Triple oc ?