Enable Piano Roll and 64-bit Mixer

[IndieP]

Hi all,
A question which I'm sure has an obvious fix.

I can't enter notes into the piano roll (Track 1) using fingers or Stylus since attaching my external xKey MIDI Keyboard, even when; (Channel Strip/MIDI Control/Input/All) is selected. Disconnecting xKey or keyboard or rebooting does not resolve the problem. How do I enable the Piano Roll?

Also I’ve observed that in (Settings/Mixer) "Use 64-bit Mixer" is unchecked, why? When should you need the 64-bit mixer?

Thanks

UPDATE: Oops! After posting the above question about the Piano Roll in the morning I decided to look at it again later on in the day when I was relaxing for the evening, and almost immediately, I noticed I had somehow enabled Velocity instead of Notes in the drop down box in the Piano Roll. I quickly changed it back to "Notes" and the Piano Roll was back on line again.

But I'd still like an answer to my question as to when a 64-bit mixer should be selected?

Thanks

[Rim]

64-bit mixer mode is disabled by default because it uses slightly more CPU power. In most cases, 32 bit is plenty for mixing.

Rim