I have a new 2006 MARIN with all the new features Sundance added this year, including super high flow pumps & new jets. It is a really great spa, but at some of the positions, particularly the lounge chair, the power of waterflow at the jets cant be adjusted at all and is strong enough to make you feel abused ! Opening the air jet barely changes the power.

In some dealer material I see that Sundance increased the flow rate in the 2006 880 models from 5 gpm to 35 gpm, a 600% increase !
This effect is so pronounced that we have started avoiding using the 2nd pump at all since everyone complains.
My dealer has been useless on this topic as he doesnt consider it a service issue.

The new Fluidex Reflex Jets and the Pulsator Jets at the lounge position are the problem, as neither is adjustable in any way.... except to turn off pump #2.
Sundance sent some supposed "low flow" jets to replace the Reflex jets; they did change the pattern some, but did not reduce the water flow power.

I sure would be interested to hear if anyone else has encountered this problem, and any solutions. Hopefully Sundance will be willing to offer some relief. I paid $7k for this spa and bought it for comfort, not for rough treatment.

Your dealer is right when he states it isn't a service issue. The reason for this is that everyone experiances spas differently, and many people prefer the stronger jets. You don't care for as much. When Sundance designed the spa, they added that second pump for the reason that you can't cover both types of customers with just one design of jets. The only work around to this is to have the ability to reduce the flow by turning off one of the pumps. That way they can cater to all types of customers and not have to design 4 different styles of jets for every spa. Just a note, opening up the air will INCREASE the effect of the jet, not decrease it. Your spa is working as it is designed to. Perhaps talking to your dealer may allow you to have your pumps replaced with a lower flow rate, but you may have to fork out for this since it is a customer requested operation.