1.4 Zetec 2002 problems

[Fiesta Chris]

just got a new car, 52 reg fiesta zetec.

a couple of problems on it.

1) when going above 70 on the motorway or when its really windy i get a really loud screeching noise from the driver side dashboard. i presume its an air leak, any idea on how/where to get it sorted?

2) the cd player makes a really annoying rattling noise when i turn it off, lasts about 5-10 seconds. the radio also turns itself on at random times. (happened about 6am the other day and probably woke half the street!)

3) the car has been running really smoothy and i've been happy with it but the last few days it hasn't been so smooth when in low gears and when reversing. it's very hard to describe the problem but it feels like its dragging its knuckles and it feels really rusty. gears 3 - 5 are fine but the low ones are not so good. any ideas? i tried filling the oil up as that was a bit low but its made no difference!