Thanks for cheching in - I seem to remember that ther have been reported problems with RadarBox reception around the Singapore area before.
No idea why that should be.
I would agree, there doesn't seem to be any logical reason. The only possibility that springs to mind it that perhaps Singapore being very close to the Equator might have something to do with it ?
I've currently got nearly 1500 aircraft showing on the network, but none at all on or near the Equator. Of course that may simply be a result of there not being any sharers in northern Brazil, Colombia, Peru, Ecuador, Kenya, Indonesia, etc, but on the other hand it might be worth investigating.