All my music is ripped in FLAC but I need to convert it to mp3 to put on my mp3 player, I've had a look but can't find any KDE4 programs to do it. Curremtly I'm using gnome's soundconverter. Anyone know of a better KDE4/QT4 app?

there's 2 or three service menu converters, I use pacpl (perl audio converter)
there's transkode, soundKonverter and probably others (not sure they're kde4 though)

I've seen the service menu's but would rather an actual program as I like to batch convert.
transkode and soundkonverter are both still KDE3

pacpl is a batch pgm with a service menu extenstion

pacpl --help

Perl Audio Converter - 4.0.5

-t, --to destination format
-r, --recursive recursively convert directory(s)
-p, --preserve preserve directory structure
-f, --formats list supported encode/decode formats
-o, --only only convert files matching extension
-k, --keep keep files matching destination format
-h, --help this help menu
-l, --longhelp complete list of options
-v, --verbose show detailed information

usage: pacpl --to <format> <options> [file(s)/directory(s)]

I have used Hyper, which also does Video, but I can't remember if it supports a batch mode. It uses FFMpeg, and has many options related to container, format, etc.