Q&A

(1)When driving approximately over 50m/h, inside my car is so loud. It is hard to hear each other. I started the car and checked engine and everything seems fine. Any idea?
(2) Also my check engine light is on. It came on, I changed the fuel cap, reset it but came on again. I went to a mechanic, he left the hood, and there was a loose hose, he plugged the hose back, cleared the check engine light with his computer. After a month, the light came on again. Please help thanks