How do I turn off my iPod Touch?
Normally, to shut down an iPod touch:

Hold down the Sleep/Wake button on top of the device. (NOT the Home button on the front.) Use the manuals link below to find the manual for your device.
Then &quot;slide to power off&quot; when prompted.

I suspect you may be holding down the Home button, which invokes the Voice Command.
From Apple Support:

How to restart

Press and hold the Sleep/Wake button until the red slider appears.
Drag the slider to turn your device completely off.
After the device turns off, press and hold the Sleep/Wake button again until you see the Apple logo.


You can download manuals for iPod touch.