Audio ads allow you to convert any audio track from your iRadeo station playlist into audio ads. Audio ads are streamed the same way like any other audio track in your station; but the difference is, your listeners player options are disabled until the audio ad completes and the next track starts streaming.
To convert any of your tracks into audio tracks, just click the "Ad" check box on the right side of the tracks under Step 2: Streaming setup. You can position your audio ad at any spot in your station stream by dragging the audio tracks. You can also allow iRadeo to randomly play audio tracks by enabling "Auto DJ" option.
See screenshot below.