Discord app is available for windows, android, mac, iOS, Linux. Download Discord App for Windows. Open any browser on your computer. Go to discordapp.com; On the homepage, you will get to see two options namely, Download for Windows and open discord in your browser. Click on Download for Windows. DiscordSetup.exe file will be downloaded.
Note that both iTunes and system alert sound volumes are determined by two settings, whereas AFAIK the output volume for Text to Speech is only determined by the system Output volume setting in the Sound preference panel. Although this is probably not your problem, you haven't made it clear either. Which are the settings for your system alerts sound volume? Is the system Output volume set to a high volume and the Alert volume set to a low volume, or the opposite, or something in between? Also, does changing the voice in the Text to Speech preference panel make a difference? iMac G5 17' (iSight) Mac OS X (10.4.4)