Q:  For some reason my microphone input combines with output and causes
    echoing problems when using the mic. 

A:  This is called: FEEDBACK and it is nothing but a normal Sound phenomenon, 
    that Microphone manufacturers have been 'fighting' with for ages. This 
    usually happens when a Mic points to a Speaker (directly or indirectly 
    - within the speaker radius).  

    Feedback is the ringing noise (often described as squealing, screeching,
    etc) that is caused by a "looped signal": A signal that travels in a 
    continuous loop. In technical terms, feedback occurs when the gain in the
    signal loop reaches "unity" (0dB gain). A microphone feeds a signal into
    a sound system, which then amplifies and outputs the signal from a
    speaker, which is picked up again by the microphone. 

    To overcome this problem:
    -  Do not point the Mic towards the speaker(s)
    -  Move the angle/axis of your Speakers so that they do not "face" the Mic
    -  Use a more directional microphone
    -  Speak closer to the mic
    -  Do not cover the Mic 'head' with your hand or mouth 
    -  Turn the microphone off when not in use
    -  Turn down the speaker volume, so the mic doesn't pick it up 
    -  Adjust the Input / Output level from your Windows Mixer  
    -  Use a headset or in-the-ear monitors instead of speaker monitors
    -  Use an audio Mixer. They are quite inexpensive nowadays: (Behringer)
       With a mixer you have more control over your sound thru Master >
       Channel > Pre-amp stage Trimmers, Attenuators, EQ, etc. etc. 
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