Ok, im at the Ruins site now (Original one) and Im listening to the ambient sounds. I can confirm that the creepy bug noises and other obscure noises does not occur in the ruins themselves, only outside them and after 2kms away from the ruins they stop. I have 2 of each item in by inventory. So this might help very slightly in identifying the sounds. I recommend others come listen too and test. Some of the noise sounds like static or even a hint of a voice here and there.
If I had the means I would post audio but I can't right now.
It's interesting but if they seriously stop after just 2 km I am not sure if that would help much. I mean if you are 2km or closer you are basically right at the ruins anyway.