PCI audio mixer for hum-free line-in recording?

Jax · 2007-02-27T21:44:46+00:00

I run XP on a old VIA266A mobo + Duron 1800 MHz processor. I am in the UK.---------------I want to plug a line-input from a tap on my home telephone line or from my audio player which runs off the mains.I get a lot of hum plugging the line input into my mobo (Syntax SV266A with a VT8235 chip for AC'97). Probably is a ground loop.Earthing one end or another of the line input lead doesn't help much. I'm told that a good way to minimise hum is to use an isolating transformer.If I get a modest audio mixer card which fits into a PCI slot, then is it likely to have an isolating transformer (or some other hum isolating device) already built in?I am thinking of a card costing about 15 to 20 UK POUNDS (20 to 30 DOLLARS). This is not trying to be audiophile but is for high quality speech files.