If it occurs consistently at the same time on the same sources, the clips are damaged or you somehow hide/ turn them off from that point on which could be anything from a specific layer switch to some effect. Also using such long audio files could be problematic and the effect run out of memory. AE simply is not the right program for this kind of stuff. As a minor, split up your layer into multiple segments...
Thanks for the advice, I will try the split up thing.
You also said that this might not be the right program to do the things I want to, so I wanted to ask if you might know a program that has the ability of making that Audio Waveform / Audio Spectrum, which is made for long clips?
Good question, but I suppose you could find all sorts of visualization plug-ins for Premiere Pro or other video editing tools. In the good old days there were also plug-iuns for audio players like Winamp that could dump the visualizers as video files. If you do a little research, I'm sure you can find enough resources.
Man, do I feel stupid..
I re-opened my project, and looked into Mylenium's advice about that I might set it to hide on a specific time, and yes, it's appearance time lasted to a little before 12 minutes.
I will try to render now, and I guess it should work now.
Thanks everyone who thought for me!