Due to Chrome's recent autoplay policies change, you may have to change the autoplay settings on your Chrome browser to enable sound and/or to prevent the program from freezing.
Please follow the instructions below for every computer that has this issue with TTRS Online:
Enter chrome://flags/#autoplay-policy into the URL address field
2. Next to Autoplay Policy, click Default and then select No User gesture is required on the dropdown menu
3. Click Relaunch now to apply the changes