HearThis playback of recorded text

The MTT has Windows 10 on his desktop computer and downloaded HearThis v.2.2.11.
However, there is no audible playback of recorded text. What could be missing?

Most likely this is not a problem with HearThis itself, but rather some kind of a setup issue with the sound settings and/or devices on the computer.
Is he able to hear other recordings/sounds on the computer? (If not, could be that he does not have speakers, they are disconnected or turned off, volume is set too low, or some other setup issue). It is also possible that the real problem is with the recording, not the playback. In the lower right corner he should see a small gray icon that looks like a headset or microphone. That indicates which recording device is active. (Clicking it will open the Sound settings dialog box with the Recording tab active, allowing him to see more details and/or select a different recording device if needed.) Above that is a display showing the mic levels. When recording, or even when just “idling” in HearThis, if he starts talking or making any sounds, the vertical bar should appear to grow and shrink as the sound level rises and falls. If nothing appears there, then the recording device is not picking up any sound, so the recording will be silent.
If there is a recorded clip for a block (even if it is silent), the play button should become highlighted when the user moves the mouse over it. If the user clicks it to begin playback, he should see that it remains with a bright outline until the playback is complete. If that happens, then it means that there is a recording and that HearThis thinks it is playing it (even if he can’t hear anything).
If you are able to go through these troubleshooting steps and still need further assistance, please reply with whatever additional information you were able to obtain from the above steps.