B&W PV1 Sub high level and low level inputs together which is default?

Hi all.

Does anybody know if you connect both Line Level and Speaker Level inputs to a PV1 Sub will it default to one or the other if for example you watch a movie and Line Level is preferred?

I would prefer a default to Line Level and that would make sense.

Another forum suggested the Sub sorts it all out inside and takes both and adjusts accordingly but it was said as more of a guess by the looks of it.

Thanks