Thank you for reaching out today and welcome to the community! I will be to help you!
In regards to your message,
- To clarify, using a bluetooth connection will allow you to play audio sources such as Youtube and Music playlists.
using Wi-Fi will allow you to play music services like Spotify and TuneIn via the Soundtouch App.
Make sure your wife and son are using your ST app account and they should be able to use your music services.
In regards to using Youtube. Try clearing the Bluetooth pairing list by pressing the Bluetooth/Aux button for about 10 seconds and you will hear a tone from the speaker.
Try pairing up to your iphone again and see if you can play youtube again.
If you have any further issues please do message again! I will be happy to assist you!