This is a difficult task. The first thing to do is filter the audio, voice depends on the frequency range from 300 to 3000 HZ, so reducing the levels of frequencies outside that range is a good start. I hope your software has such filters. If not, I think there are some free audio editors that can do the work. Audacity is one.
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System - Athlon 1.4GHz, Win98, Hauppauge PVR250 receiver and compressor.
Software -Magix Movie Edit Pro 10, Nero 6 + NeroVision Express, Moho 4.61, PSP 8.1, Bryce, Quicktime 6.52 pro, Goldwave 5, DVD-Lab.
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