Force restart iPod touch
If iPod touch isn’t responding, and you can’t turn it off and on, try forcing it to restart.
Force iPod touch to restart
Press and hold the Sleep/Wake button and the volume down button at the same time.
When the Apple logo appears, release both buttons.
Note: If iPod touch still doesn’t turn on, or if it gets stuck during start up, see the Apple Support article If your iPhone, iPad, or iPod touch won’t turn on or is frozen.