Cannot join group calls if invited, but able to from the group chat link

I've had several users experience this, and it happened to me recently. If a group chat exists, or is created, and the new end user is called (Teams pop up for incoming call) they are not able to join the call. The screen pops up but is all black and they cannot hear, not be heard in the meeting. If the user goes to the group chat and uses the button to join the call in progress however; they are able to join without an issue.