Data-type changes when data enters cluster

I'm having a sporadic problem with data-type changing when data enters a cluster. Certain times when the input value is a number (in this case 516), I instead get either int: 516 or double: 516. I've seen this happen in many instances, but until now I've regarded it as a mere curiosity since the data have always been automatically converted back to integers or floating-point decimals by components within the cluster.

Today, however, the conversions failed and errors ensued:

In this case, I was able to temporarily solve the problem by recreating the cluster's content in the main workspace. Because this happens in some but not all instances, I strongly suspect that this is a bug, but if not I'd appreciate in any insights.

(On a tangential note, what does 'double' mean in this context?)