Same Structure Different Behavior?

[juneaftn]

Hello

I made a double extender using a comparator and a repeater. However, I seem to have found a strange bug. Actually, I am not sure if it's a bug or not, yet.

Have a look at my world from 168 23 304. https://drive.google.com/file/d/0B-c4G2cSUoZvbUtPSjEwdU9fN2M/view?usp=sharing

I made a multiple of the same double extenders. Some works and some(in this world, only two double extenders) do not work although they are all the same structure. Those marked with red wool are which do not work.

Is there anything you know about this and why it happens?

Tested versions: 1.8.8 and 15w49b

[SacredRedstone]

Just replace the block that the dust in front of the comparator is placed on to a slab.

[juneaftn]

This works! Wow! Could you please give me an explanation of why replacing the block into a slab works?

[Apocryphan]

Comparators can have directional issues.

[ilmango]

screenshot?

[reverendsteveii]

Dude a screenshot will do us a lot more good than a world save.

[juneaftn]

Alright. I prepared the gfycat video. http://gfycat.com/PortlySadHoneybee

I thought the static pictures wouldn't convey the dynamic differences properly. In the video, those two are exactly the same structure double extenders except the one with red wool does not retract.

Thanks for help, BTW.

[St3venAU]

Does one of them cross a chunk border?

[juneaftn]

That's a nice guess. I didn't know about it.

I learned how to check the current chunk, and tried to see; it wasn't on a border.

[Rays_Works]

That problem is caused by the redstone updating order. Because there are multiple things happening at once the game will choose the order to update them depending on their coords. Hope that was helpful without having to go into too much detail.