I didn't think so, but I thought I would throw that out there.
By having it plugged into the surge protector.
Does this effect the power output?
Or
The watt output per channel?
The way it could effect power output is to limit high demand situations.
In other words if you are using the XPA-3 at medium levels, there will be absolutely no effect, but if you start pulling more power than the strip allows, the strip becomes a limitation.
For normal speakers in a normal size room, I would not expect this to be an issue. But if you have inefficient speakers that demand lots of power, the strip could impair performance.
Not that the capacitors handle transient peaks, so the demand would have to be comparatively sustained to cause an issue.
If you tell us what your speakers are, how large your room is, and how loud you listen, we can generally let you know if you have reason for concern.