Decrypting audio downloads

[spiritgumm]

Wondering how to decrypt downloaded audios? It's not playable when I download to my PC. Mediainfo indicates it's an encrypted audiofile. It's intended to be downloaded to a mobile device with the provider's application installed (which isn't available for desktop PCs). I don't know anything about decryption, except you might need a key code. Maybe a code is included when downloading to a mobile device, and could be used with decrypting methods?

[2nHxWW6GkN1l916N3ayz8HQoi]

You might consider giving more info so people can help. What app is it? What's the mediainfo report? Can you play the file offline after downloading it to your phone? If you have the file on your PC, can you upload it somewhere so people can see what kind of encryption it uses? How did you manage to obtain the file from phone app, did you root phone + network intercept?

[spiritgumm]

Thanks for replying. There's a yellow banner on forums here discouraging people from discussing streaming sites, so I was acting conservatively. I was told that if I mention the site name and they complain, then the topic will be deleted.
I downloaded the audiofile (considered an audiobook) from the website with browser addon Turbo download manager, not from a phone. I have a smartphone for emergencies, but the plan doesn't include unlimited data downloads.
I see topics about decrypting from specific sites (ie Audible - which is Amazon), but I haven't seen one for the site I'm accessing (hoopla, with a city library login). I know it's possible because I gave a link to someone who downloaded/decrypted a file, but he's uncommunicative and apparently won't share his methods. Audible might have the same audio files as hoopla, but the latter is free for me.
I can upload the file to mega to be downloaded since it's relatively large, 338 MB.

Mediainfo:
General
Complete name : D:\Downloads\unknown.m4a
Format : MPEG-4
Format profile : Base Media
Codec ID : isom
File size : 339 MiB
Duration : 5h 54mn
Overall bit rate mode : Constant
Overall bit rate : 134 Kbps
Encoded date : UTC 2020-11-09 22:06:21
Tagged date : UTC 2020-11-09 22:06:21

Audio
ID : 1
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : LC
Codec ID : 40
Duration : 5h 54mn
Bit rate mode : Constant
Bit rate : 128 Kbps
Channel(s) : 2 channels
Channel positions : Front: L R
Sampling rate : 44.1 KHz
Compression mode : Lossy
Stream size : 325 MiB (96%)
Tagged date : UTC 2020-11-09 22:06:21
Encryption : Encrypted

[johns0]

If those files are encrypted you won't get any help from here,this thread is closed.

[Baldrick]

It's okey if it's from a free service.