Your post has been split into a new topic. Though what you read in the prior thread seems to be the same issue, there are actually many reasons for lack of audio - from incorrect settings to bad files or bugs in specific VP versions. Most of the latter have been fixed.
Please share a file of two that has the problem and someone will look into it. What is the version # being used. Look under the MENU (top-left), HELP | ABOUT to find it.
Upload the file/s to a free server, such as Google Drive or MS OneDrive, get a shared (public) link, copy the link and paste it here or to me in a Private Message via the mail envelope in the top-right corner of this forum. When using Google Drive, if necessary change "restricted" to "anyone with link can view."