When I record using my microphone I hear "pops" and 'hissing" when listening to the playback. What can I do to prevent this? The moment I plug in an external mic (a Sennheiser) a low level rumble starts immediately recording starts. This becomes part of the audio track for the video and is ruining it. Any suggestions Bob McCaw

These mini video cameras are great for a lot of reasons, but the drawback is the tiny buttons and connectors, like the microphone input. It's probably actually a stereo microphone input.
If it is stereo (check the manual), then try using a stereo adapter, where you plug the adapter into the stereo mic input on the camera, and then plug the single microphone into only one side of the adapter ... then copy the audio to the "missing" side later in production ...
Alternative: record the audio separately onto a decent quality audio recorder with proper microphone jacks, then find the corresponding audio and synchronize it in software production. This is often how professionals do it, and one of the reasons you see the familiar "clapboard" snap at the beginning of movie shoots ... clapping your hands on camera right before you shoot will give you a visible action that will correspond to a peak in the audio soundwave that you can match up to synchronize the audio once you put the video and audio into your computer.
Another alternative - new item these days is an audio interface for video cameras that is basically a small black box that mounts onto the video camera or tripod, plugging into the tiny input on the camera and providing XLR microphone inputs ... just go to Borders and pick up any magazine on video production, you'll see them advertised all over the place ...

Good luck, hope I have helped in some way!

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