Delay using MIDI keyboard

Hey folks, When I play a note on my Roland A49 there is about a half-second delay (otherwise known as "latency"). This delay is absent using, for example Podium--and no alterations of the external soundcard buffer, have been made when switching to Reaper. It is impossible to play the keyboard this way. I have rite-cliked the record arm and selected 'monitor sound'. Any advice? Thanks much!

I would double check the buffer settings within Reaper, to make sure they didn't possibly reset after changing daws, press Asio Configuration to get to the actual audio card control panel. And then check for latency-inducing plugins, such as mixing/mastering stuff, go view-performance meter and then look under PDC(plugin delay compensation).

Delay still there. 

Oh well,but nothing has worked, not even running an effect-less instrument in a new project. I'll keep trying. Best, thanks much for your response!