Instead of playing a sound when a reminder is due you can also let CalenGoo speak the title of the event. Just turn "Settings", "Reminders", "Show pop-up window" and "Speak event title and location" on.
Installing Text to Speech
If it doesn’t work, i.e. no text is spoken, then please check if you have a text-to-speech synthesizer installed, e.g. you can install Google Text To Speech.
Installing language packs
If the wrong language is used to speak/pronounce the text, you may have to install additional language packs for Android’s Text-to-speech output. Just start the "Settings" app and tap on "Language & input", "Text-to-speech output", then on the settings button (please see below), "Install voice data":