blowers issue when filter is running

[Racker]

Have you tested the line going from the pump to the spa for cracks and blockages?

[bksbeat]

Last night I swtiched the pump valve to spa with the filter on and the water came flowing strong through the spa blower so there is defintely nothing wrong with it. I have it always normnally set on pool and it has always had water come out both spa and pool blower. Could it have anything to do with the thermostat on the filter / it almost seems (and I am speculating) that is a power strength thing where the pool blowers are dominating and all the power is coming through there and little power for the spa??