Dear David__B
Thank ypu so much for your interest and help.
I am not using a VPN service. You look a VPN icon in my screenshot but it is dissabled.
I tired several attemps to solve this topic using ADOBE EXPRESS / animate app. Finally, I searched other possibilities as reason for this issue and I found a mistake (my mistake) because I was uploading an audio file extension (*.m4a) forbiden by ADOBE EXPRESS. (A.E. allows MP3, AIF, WAV, MP4). Thus, Trouble was solved using the correct audio.
Sorry
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