The ornamental design for an audiomixer, as shown and described.
FIG. 1 is a perspective view of an audio mixer showing our new design;
FIG. 2 is a left side elevational view thereof; and,
FIG. 3 is a right side elevational view thereof.
The broken lines in FIGS. 1, 2 and 3 define the bounds between claimed and
unclaimed subject matter and form no part of the claimed design.
Similarly, the surfaces of the audio mixer not shown form no part of the
claimed design.