I've been experiencing this issue for two days. Basically, I get the error notice that says, "Something broke and got grounded." every time I try to enter a TTS voice line. I tried bypassing the issue with the usual methods (that being inserting spaces or simply just altering the text), but they didn't work, no matter how hard I tried. And it doesn't matter which voice I use at all. I can't think up any reliable ways to bypass the issue.
(In one of the attached screenshots, you'll notice I'm using the Joey voice. I checked, and it has the "(old)" suffix attached to the end.)