Yup, unfortunately. Also, I didn't show that in the example, but try adding custom { } stage to the material your object uses, and you'll get +1 drawcall and +base amount of triangles again.
Haven't worked with sound shaders yet, but I remember I made a melody for Deadly Shadows, where I could use either several parts (different files) looped and chosen at random, or at least the same file played at different pitches. If you can't have such thing in TDM, that would be a good idea for improvement.