Wood will reduce signal strength somewhat, but not usually enough to matter. That’s why a signal from the hub can reach a device a couple of rooms away. The following graphic shows the reduction in signal strength from different types of materials:
One thing to note, however, is that if the entertainment cabinet is painted or shellacked, that might reduce the signal further. In particular, those red lacquer Chinese cabinets that some people use have iron oxide in the paint, and are terrible for getting signal through.