Presenter Viewing Materials when playing a uploaded video results in video starting over

I used the new version of the GoToWebinar platform for the first time today. Part of my broadcast was sharing a pre-recorded talk. I did so from the main Sharing icon at the bottom of the Organizer dashboard. Everything was working great until 20 minutes into the recording, when I chose to click on the Materials icon at the top of the Organizer dashboard to confirm that the pdfs I uploaded for attendees were there and displaying properly. The pre-recorded video was also listed among the Materials list and for reasons unknown the platform seemed to switch over to the pre-recorded video among the Materials list and started playing the video again from the beginning. Luckily in this new version of the platform you can now fast-forward a video (thank you for that!), so I quickly moved the video to the spot where we left off. After the webinar I set up some test webinars to confirm if I may have done something wrong, but the same thing continued to happen. Is this a known issue? Is this user error? Is there some function I'm not aware of that I can turn on/turn off so that I can click on the Materials icon with peace of mind and not worry about disrupting a video that is currently playing?

moderator edit: title for clarity