Signal block detection issue

[poster983]

Signal blocks periodically do not detect that a cart is in said block.
I've noticed that it fails about 30%-40% of the time.

I'm not sure if I'm doing something wrong on my end but I replicated one of the tutorial examples in a superflat world and was getting the same results.

Using: Signals-1.12.2-1.4.1-30-universal.jar