uspino

As a journalist, I used to have a Pocket PC Phone that I used with a pro microphone (with a Line Matching Transformer) plugged into the headset connector. The quality of the recording was amazingly good at WAV, 16bit, 44100.

I just bought a 4705. Using the same cable set into the headset connector allows the use of a pro microphone, but the quality is far from being satisfactory due to something I can not quite understand. When you record into the 4705 (using any of the software applications available or even the Notes recorder) the signal sent from the external microphone gets mixed with the internal sound and everything gets recorded, thus creating a constant background noise; the mic signal is on top and strong, but the hiss is unavoidable.
This will explain better what I'm suffering: if you hit "Record" to record the sound from the Microphone, the "clicks" get recorded too if they are activated in "sounds and notifications". And if you play a song in Windows Media while recording in the other application, the song gets recorded too, even though the speaker is muted because a jack is plugged into the connector!

My question is: is there a "Mixer" application or a registry twaek that allows me to select the recording source, as I can do in Windows XP?

Can anyone think of a solution for pro sound recording? I hope there's something besides the expensive and bulky Core Sound PDAudio

Thank You.