Through the BTI album I noticed a number of them just cut off, and then a clicking and ringing sound is heard. Maybe this album is supposed to be someone flipping through cassettes for a number of songs, not every song being a cassette, which would explain why the songs almost always get more chaotic, showing the wear and tear if the tapes. Now I might be stretching here, but in the end of Zealots instead of a click we are greeted with crikits and a plane, which I believe is actually real world sounds. The songs with clicks are Crawl, Death by Numbers and Urn, with Trolls just ending with library, which I think is just him turning the TV/Radio, off or on. That leaves us with four cassettes, starting with Crawl, Worldstar, Navigator and Pink Toes in order. Here's where the stretching comes in, maybe someone is listening/watching to these in 3005, I think the Firefly guy, and turns it if in Zealots so he isn't found by the plane, and continues to listen after. Or maybe a little before 3005 because in Earth he says 3005 the year we fear only god will survive, so the person is just biding his time until his believed demise. Tbh, I really am stretching at the end here, but I think the top half is plausible.