04 Cruse Control intermittent

[Stockintoshockin]

I have been having random intermittent cruse issues. When driving usually when the vehicle is load more, such as 4 people and luggage, the cruse light will flicker for like .2 seconds and the cruse will drop. 99% sure it not brake petal/switch related. Most of the times is acts up are when I hit a dip in the road and it seems like the car coast for second or almost goes to engine brake then reapply throttle. Also on one occasion just is straight line flat driving I would set it and it would kick out almost immediately, the more I set it the worse it got in all cases. I did read 2 other posts about this exact problem most suggested it was related to brakes, but the dash light will not flicker if the brakes are applied. If any had resolved those previous posts or knows something that would be greatly appreciated...2800mile road trip is nearing and I would really like my cruse to work for sure. thanks in advance

other info
2004
stock except the radio, speakers, and K&N
150k miles
4 speed auto