The control and audio heads are two separated heads but located on the same place, as you can see in Figure 5. The cleaning process is the same as the one used for the erase head: just rub a cotton swab with alcohol on them.

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Figure 5: Control and audio heads.

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Figure 6: Cleaning the control and audio heads.

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Figure 7: Cotton swab after the cleaning process. Yes, our VCR heads were dirty!