[gunner45]

There is an upstream signal problem and the 3dB attenuator might be part of the problem - but only if your upstream power is already marginal. If your upstream power is above, say, 48 dBmV, the attenuator is very likely contributing to the problem.

Power off the hub, remove the attenuator, check that all connections from the hub to the wall socket are finger tight and that the cable is not damaged or kinked, and reboot the hub. If upstream power drops to ~43–47 dBmV and downstream stays within safe limits (-6 to +10 dBmV), leave it off, but if downstream shoots above +10 dBmV then a tech needs to be called out. He can do things like replace F‑connectors both at the home and cabinet, and measure power levels at both ends.