It's been said that you need to open a separate window to transpose an audio file. This is not so. If you press the +, or - transpose button, the screen shows an icon labeled one of three choices:
MASTER
KEYBOARD
AUDIO
You can simply touch the icon, and select what it should change, and it will stay that way ... at least until you turn off the kb. Haven't gone past that step so far.

For me, I like it set to MASTER. That way, everything changes - if I choose to give my voice a break, or sweeten up a sound with a key change.

I will try again,but the manual indicates that audio is excluded,and you have to go to Pitch Shift and Time Stretch.

nope - just touch the icon, and pick "audio" ... I THINK. Damn - now you'll make me check again tonight!

Bernie is right. Menu > transpose permits transposing Master, Keyboard, or Song (Midi).
Now to find Pitch Shift.

When you call up an audio file (song), there is a very small area near the middle of the screen that lets you select pitch shift. It's the only way to do it. You can do midi files the way Dave said, but not audio.

Very good Don. Like a needle in a haystack.
Two steps
1. call up the audio (song)
2. Press Player
Pitch Shift in tiny font

YUP - I stand corrected. I was thinking the "song" icon was for audio as well. My bad!

When I sold the SX900 and then bought the Genos, I spent about ten minutes trying to make the audio player work, to no avail.
Finally, I realized that the display was reversed. The audio player was on the left side of the screen on the SX and on the right side on the Genos. Or maybe vice-versa. I don't remember.