Excuse my rudeness..but why worry yourself with being 'polite' about it? I see nothing polite about a provider faking their enjoyment with someone who has contracted them for their time. Being a provider myself.. I find that sort of thing utterly distracting, uncomfortable, and an absolute turn off.  

"You can go ahead and just knock that shit off"..seems exceptionally polite to me. =)

AND!!
 I just need to add in, per your comment of avoiding all those who specifically advertise a PSE..
I'm both a GFE and PSE provider, although it seems that most of my encounters lean a bit more towards the "PSE-ish" sides of things.  
 Never in my life have I created unnecessary and/or counterfeit noise. Maybe its just my personal understanding..but 'PSE' doesn't necessarily indicate that a provider will be simulating the frequently over-embellished recitatives that are often component of a pornography film.  
 I believe it better describes the type of acts that may or may not be incorporated - and redundant commotion need not be included. =

Hit me baby one more time

1. Shout cut......take 2

2. Tell them you have a thing for silent movies and would they be happy to play the part  

3. Take a gag along and say you're a novice at bondage and would like to try it out

4. Each time they start with the pse verbal, accidentally poke them in the eye with your cock

5. Tell them you suffer with tourettes and if they swear or say rude things it will set you off

I'll be interested to hear which one of the above works out for you

hmmm

Send me a PM I want to know if we met the same provider