Many users don't know that iOS only allows playing sound from internal music apps, and will mute the sound from other apps. In this case, you can hear the sound from iPad's internal apps, but you won't be able to hear the sound from another app like Splashtop. The following instructions will help you determine if this is happening in your case.
Please follow these steps to verify that the mute function is enabled on your iPad:
1. Tap Settings > General.
2. Under Use Side Switch to (shown below), select Mute. Then select Lock Rotation again to fix a bug from iOS.
3. Double-click the Home button to display recently used apps.
4. Flick from left to right along the bottom of the screen. A sound control bar will display:
5. If there is a slash across the Speaker button as shown above on the left, tapping it can enable your sound function again.
Please also view this article from Apple for more details:
https://support.apple.com/kb/HT4085
If you still can't get sound on your iPad, please also check the settings on your Windows or Mac.
Please view the following links to confirm that the Streamer side has been properly set up as well.