Audio's partner (5)
I believe the answer is:
video
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">audio's partner</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for video that I've seen before include "Recorded film cassette" , "Relating to televised images" , "Visual element of television" , "Recording tape for visual images" , "Who killed the radio star? (5)" .)