I found one in Extractor Plant in the Upper plains (called Blue interrogation) - after destroying the facility, go back in the room where the bellsprig is and go upstairs and in one of the little rooms the audio log is on a box :)
There is one more in upper planes. In a crashed dragonship. It's unmarked location. And there is one more after finishing the main story in a bunker where Mercer's base was.
@altersurge7770 it's close to Stone Processor Alpha, on an island on the Twisting Pillar River :) the log is inside the crashed ship just above the secured equipment container :)
There are none at the second HQ if you get them all at the 1st. Mine is completely empty and grabbed all of the HQ ones early...or do they appear later in the story?