Hi Shaun-OC,
Thanks so much for reaching out through Apple Support Communities for help with your iPad and external audio devices. We'd love to help.
Have you had an opportunity to restart your iPad and can connected devices since noticing this behavior?
As there have been several recent updates, please let us know the exact version of iPadOS installed. This can be found under Settings > General > About.
How many external devices have you tested, and how are they connecting to your iPad? If possible, are you able to test if audio plays when your iPad is connected to other external devices, such as a set of headphones?
Let us know if the information in this guide helps:
Play audio from iPad on HomePod and other wireless speakers
Have a great day!