People who are starting out on their first VoC programs often are not sure how much to write down and how to keep track of attributing comments to different speakers. While there are benefits to understanding the customer's responses and the context of their words, this is not your primary responsibility. Your main responsibility is to provide a verbatim transcript of the interview session, capturing the customer's responses in a way that sounds like the customer speaking; in other words, capturing the customer's voice.
To do this, you need to try and write down the interviewee's responses without attempting to interpret or translate their responses in any way. Try to capture as much of what has been said as possible. Any change you make to the words the customers says takes time and thought. Attempting to process and summarize what the customer has said tends to put you into the interview and this is not what you want. When you try and summarize what the customer has said...