Pressure Switch?

When pump is on I have a slight power flunction every now and then and when the pressure shuts off there is a slight hesitation in the control box. Just started today. Control box and breaker are new. Pump is 3 HP deep 800' 4" submersible. System is over 10 years old with original pump and pressure switch. Could the contacts in my pressure getting worn out or dirt?

Maybe a little more info I can give.
My computer was running out of battery juice last night so I had to be real short. Yesterday the pump did not come on when it should have (pressure was getting lower than normal) so I took the cover off the control box and some mice had taken up residence so I fugured they had messed something up. I had a spare control box so I hooked it up and the pump ran for a few minutes but did not sound normal and then the reset button tripped and shut everything off. I use my breaker alot do to lightning and I thought I had wore it out and again I had a spare so I changed it out. The pump started back up and ran until the pressure switch was satisfied but it still had a little power fluctuation and when the pressure switch tripped there was some hesitation in the controller before the pump shutoff. Definitely not normal sounding and as the wife would say I have become one with the well as a monitor it quite a bit to help costs down. It can be an expensive guy to maintain. Would it hurt to lightly hit the pressure switch contacts with some emery paper? Any help would be greatly appreciated.

Alright one more thing and I will shutup. I went down this morning and looked at the contacts in the pressure switch. Did not look to bad but there was a little corrosion on the springs behind the contacts. I tried to lightly hit them
(contacts) with some fine sand paper (almost impossible to get to) blew everything out and then turned the power back on. I pushed the contacts together to get the pump to start and it ran until shutoff but the pressure switch was making a louder than usual buzzing noise and fluctuating sound. A sick sound is about all I can say. I am hoping none of this is pump related. Thanks for any help.

Sorry but none of this makes any sense to me. If you have a Deluxe control box, the main relay in the control box may be sticking but, that is a long shot.

1. The installed control box must be the one that is specified for the pump motor. If you install any other control box trouble is likely.

2. If your electric supply is fluctuating too much it can ruin any motor.
....The power company is responsible for ensuring your home receives a stable supply. Get them involved if it is not.

3. If you have a whole-house water filter, replace or remove it.

4. Use a voltmeter to measure the voltage drop across the switch.

5. Use an ammeter to compare the pump motor draw to the factory specifications.

If you don't have the knowledge, skills, and/or tools to do these things, it's time to call in a pro.

Yea I will probably call my well guy Monday. The control box is the same as the old one and I did put the filter on bypass. The pump came on a little while ago but shutoff before the pressure switch opened to cut it off. Probably something tripped the reset button. Could the motor be going bad and causing this? You can hear fluctuations in water flow which may be from power fluctuations or the motor is doing something. The power to the light in the pump house remains steady so I would think my incoming power is good.

You can troubleshoot with an ohm and amp meters.

http://www.franklin-electric.com/business/WaterSystems/service/AIM/page-43.aspx

You either have something wrong with the cable or motor is my guess. The mice in the control box may have caused a short etc.. But I'd measure the voltage at the switch too.