Download
Audacity, or any other sound recorder and editor that can give you the spectrogram. Record the sounds that you think might have something hidden in them, then take a look at it.
As for the Thargoid Probe spectrogram, the best explanation I've seen so far was that it's a decoding key to the tight-beam transmission that the probes send. The four corners are binary for the order in which they are sent, the four quarters show what is being sent: temperature, gravity, radius, atmospheric composition.
An added extra fifth value is the distance to Col 70 Sector FY-N c21-3, which is locked.
I believe the biggest question we haven't figured out yet is why does Merope and Merope 5 c in particular feature prominently in the Thargoid items' behaviour, when there is nothing there. Lots of players have scoured the surface visually before and found nothing of note, and the new magical DSS found nothing either.
So basically, all avenues of investigation that we can pursue (so, no locked systems) have been completed, and we're waiting for FD to do something.
As for the peaceful Thargoid interaction they said, that just might be feeding them cargo, most importantly meta-alloys. However, that hasn't shown any signs of a global effect.