If there is such an issue, it no doubt will be corrected. But to investigate please upload one or two of your (raw) mp3 files that have not been tweaked.
The process is simple. Just follow these steps...
Upload the file/s to a free server, such as Google Drive or MS OneDrive, right-click the link and Share or Copy. Copy the result 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, click SHARE | SHARE and change "restricted" to "anyone with link can view.**