Its not a hard to thing to add audio to any of our equipment, i'm just not a huge fan. And by I'm.. I mean me (Jeromy Jones) President of Paranologies. Why you ask? Well for me its really an opinion, but I don't like annoying noises going off when i'm trying to be quiet and observe in silence. Also equipment that makes noises can disturb any Evp's you may get. However I know why it would be useful.. say your in another room and not watching the camera's and a Parascope goes off... well you missed it because it didn't audibly alert you. Yes I could make audio standard in most of our equipment, but if there is anyone else like me, I would rather just charge a small fee and add it than removing it later. The Paramid is the only Item I have with audio that is standard.. and that is because the display is not easy to read on camera. So there ya go, I've been asked to do this for many years now and I finally caved in... Hope your happy :)
Add it here- http://www.paranologies.com/collections/accessories/products/add-audio-to-a-new-item