The issue may be a problem with the video track encoding on the source encoder, or in how the audio/video is aligned coming into Wowza. So that we can investigate further, do submit a support request to
firstname.lastname@example.org from an email address that is listed as a valid support contact for your Wowza account. We would need conf and logs files, and URL links from you, and this would be better handled through a ticket. Please include a link to this post for reference.