@Setanta,
You are probably right about that, Setanta.
I was trying to find a solution to k's noise problem.
But I knew she most likely wouldn't buy it!
Maybe there isn't a solution which suit humans and mockingbirds at the same time?
They are both sharing the same environment, after all.
Maybe earplugs are the best solution for humans?
And as we have seen, birds all over the place, are very good at replicating all variety of sounds which they hear around them.
Perhaps we should just admire them enormously for their incredible skills ?