Mixer : no signal passing through panner

You are routing a strip into a bus through a panner, but you have no signal on the bus.

In Version 10, channel types were introduced to help multi-channel panning.
If your strip has no channel type, it will not connect correctly on the bus.
 

Click in the input zone and set a channel type, the signal will connect on the corresponding bus channel. 
 

Same channel type menu is available when you create a new strip.

If you still don't have signal or don't get the expected signal, check the bus trim icon in the mixer.
If this icon is yellow, level trim is applied.