Condenser Mic Noise Problem on SoundCard
Do note that the microphone seems to be connected to a 'professional' audio plug - which normally means that the plug has 2 signal lines and the shield. The audio is then transported symmetrically over the 2 lines.

At the other end (sound card) you need a balanced-to-unbalanced transformer, else interference will couple into the line.

I've found very little technical information on the HTDZ - none about if the microphone is balanced or not. I just assumed that all 'professional' microphones should be balanced. Also, the XLR connector is for balanced lines. I'd be interested to know how you found if the HTDZ is unbalanced. 

Here's good article about balanced lines, and how to correctly 'unbalance' them at the other end. Mostly, this is done by a balanced electronic input (which most soundcards do not have). This article and this, even more complete article have several such circuits.

Note that some articles, including an example in the first article suggest that you can couple a balanced source to an unbalanced input. I would not recommend that, unless you are sure there is no strong interference.