Im still a beginner at AE but I feel i have a decent grasp on it, but I will probably murder all the termonology in explaining! :-)
I created a short animation that loops smoothly. I dropped that animated comp into another longer comp. I enabled time remapping and the LoopOut property for the loop to loop inside this other comp (as instructed by tutorials). I stretched the bar in the timeline to the full length of this comp and my animation loops while inside this comp just as I wanted.
The only difference is that when it get to the end of its first run, it blanks out then comes back. It keeps doing this and its not consistant. First it blacks out after the first 4 frames (which is the actual length of the original animation), then it does it after 8 frames, then 16 frames before it returns to the beginning and loops over again.
I have this happen every now and then for reasons I dont understand but as i fiddle with things, I seem to fix it but cant understand why. This one I just cant seem to get through and not sure what I am missing. Hope I explained it well!!
Extend the out point.
Im not sure what that refers to, but I have extended and shortened both the comp that contains the animation and the comp with the comp that has the animation. It just causes the animation to disappear at different times
Time in AE is fluid and frames are sampled at the beginning of their duration. You are introducing tiny offsets somewhere that accumulate over time, resulting in those shifting patterns - after each cyle the rounding is just different, hence it seems to "grow". Make sure your tiem-remapping is exact and you do not introduce framrate mismatches.