No matter how many times I try to transcribe the morse code by ear, I end up with gibberish that doesn’t work with a Caesar cipher. Here’s another attempt:
:
MUVHURPSWPRASGUK<AA>SUMQYMIUIYMPPS<AA>PSWPRASGANQAYITA
The angle brackets are added automatically by the translator, so they’re not a part of the code. The AA and AS could be there intentionally, but it’s difficult to say; I do seem to consistently catch them when listening, so I believe they are correctly transcribed.
My theory is that the text is partially or fully encrypted with a method other than a Caesar cipher. Perhaps something from the image acts as a key for it?
But without a clearer audio file I don’t know how much more I’ll be able to get out of this – if someone could clear out the background noise and keep the morse clear, I’d have more success, but it’s tough as-is.