Generate Speech and copyright - can I use generated speech on TV?

The specific information about the Audition app is here: Text to speech

You will note that it says that there are commercial restrictions on the use of the results, and these are all different, according to where you got the voice from. So if you use the Microsoft voices, then you have to ascertain from them whether there are any particular restrictions on their use. The relevant information about that is here: Microsoft text-to-speech - commercial use. If you use the Microsoft voices, it would appear that there are no restrictions relating to your distribution of the results at all.

It depends which voices you're using as they're generated by the OS you're using.

You are able to load in packs to your system and use those. Some packs may be available to purchase and have favourable license terms. The Apple voices, for example, cannot be used for commercial gain - see macOS Catalina docs:

F. Voices. Subject to the terms and conditions of this License, you may use the system voices included 
in the Apple Software (“System Voices”) (i) while running the Apple Software and (ii) to create your own
original content and projects for your personal, non-commercial use. No other use of the System Voices
is permitted by this License, including but not limited to the use, reproduction, display, performance,
recording, publishing or redistribution of any of the System Voices in a profit, non-profit, public sharing
or commercial context.