V0icE

Challenge:

A friend of mine sent me an audio file which supposes to tell me the time of our night out meeting, but I can't comprehend the voice in the audio file. Can you help me figure it out? I want to hang out with my friends.

Download file
SHA1:3173700e9ba2f062a18707b375fac61049310413

Solution:

After conducting simple checks with strings, exiftool, etc to locate the flag we open the file in Sonic Visualizer and added spectrogram layer, which revealed the flag:

The accepted flag was, flag{1257}