So far, everything is fine with my MC6. I am still learning how it works. Dragging sounds over, seeing what different combos sound like etc. I got the midi (Axiom 25) hooked up and running. I think it took about 30 min, I was expecting a ordeal. lol.
 
The midi sounds like the vol has been turned down, but its most likely knobology and the thread about setting levels probably is my issue.
 
The big problem for me is deciding what keyboard to buy. I mean the last time I played was the 70's, where you had a choice of a electric piano that was just a electric piano and a analog synth or a analog synth. ok, Im exaggerating, but you know what I mean. So many features!
 
I keep looking at the Yamaha PSR 433, or a YPG that has 76 keys. decisions decisions
 
synth (maybe next year) a MM6 or  microkorg. which direction to go....
 
Doug

As far as keyboards.... get one that you like with the features you want.

Understand that in the end....as far as MC6 is concerned.... midi is midi and it doesn't matter if it comes from a $3000+ workstation or a $69.95 Walmart special.... so get the keyboard that you will enjoy playing. 

On the midi volume issue... be sure to look into the GUI of the synth. Many synths if not all of them have some sort of master volume control in their GUI.... and for example... the one I have and use in Kontakt is set at about 60% or so.... which depending on the sample I have chosen could be very low in volume. I simply click and drag it up a bit and I can hear just fine.  IIRC, even TTS has a master volume on it. 

Find the master volume on the synth and turn it up..see if that solves that problem. 

I ordered the Yamaha PSR-E433.

I never thought about it as "midi is midi" but it makes sense.

I will check the GUI when I get a chance, hopefully tomorrow.

Thanks

let us know how it goes....