07 Hyundai Elantra buzzing feeling in gas and brake pedals

hyundai
vibration
elantra

#1

I have an 07 Elantra GLS automatic about 25000 miles.

so since about November there has been a buzzing type feeling (I can feel it in my foot) both brake and gas pedals and little bit in steering wheel (like the feeling of an electric razor) Moving or idle the feeling is there, though it more noticeable at highway speed; also there is a rattle in/near the dashboard driver’s side.

I’ve been to my mechanic and the dealer but neither have been able to pinpoint or even acknowledge there is a problem. Tires have been rotated and balanced, alignment is fine. I know something isn’t right but don’t what it is and if it could be dangerous. I’m hesitant to drive it for long distance. Any ideas will be greatly appreciated.