Turbo issues?

[Marty-g]

Hi all, I was hoping someone may be able to help. Recently my car a 130 tdi has felt a bit sluggish in the lower Rev range, it feels as if the turbo is not spinning up very quickly and in first and second gears it just doesn't pick up like it used to. It seems better at higher speeds but it is still just about detectable? I've also noticed that the car has also stopped letting out that kind of sighing noise when I change gear, if you know what I mean. Could this be coincidence? I'll have a poke around tomorrow and hopefully find a loose pipe or something, but if this sounds familiar to anyone i'd much appreciate some input. Cheers guys, martin.