windows 7 volume

[Beans on toast Dave]

been using windows 7 build 7100 for a few weeks now
been very impressed so far
just somthing that you might be able to help with

when playing video files, on some of them the volume is really low
never had a problem with vista

the only difference is i have no extra codecs or ac3 filter installed

is there anything i can adjust in win 7 to up the volume so they all files play about the same level without installing extras

if not whats the best thing to install?


thanks