Hi Lene,
So good to hear from you! I think I have a way to help I just discussed with the team yesterday. There is a button that appears when you’re sharing your screen in the picture-in-picture box that pops up while sharing. There is a screenshot of where it is below.
It allows you to temporarily mute the audio share while you and your learner talk, then click it again to share the audio again and click play to keep listening/watching. It's often necessary because, as you mentioned, audio share works a little too well and
can create an echo when it does. I hope this helps, but please let me know if it doesn't resolve the issue for you.
FYI: If you happen to be sharing a video on YouTube, we have a built-in YouTube video sharing option that does not cause the echo and is a great experience as it eliminates ads and plays the audio seamlessly on your end and the learner's end separately. There
is a screenshot of where that option lives below in case you didn't know about it. It add the video to the canvas and you watch it there with the learner.