Dull speaker
I believe the answer is:
bore
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">dull speaker</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for bore that I've seen before include "fatigue" , "Fast-running water" , "Drill or weary" , "Drill to be tiresome" , "Hollow out; dull person" .)