Very fine subject, I'll step in!
I am currently working on some artistic research, funded by the Ministry of Culture in Denmark, partly on that. I somehow am looking into huge areas within sound and music that lay uncovered, mostly because of a lack of distance and/or imagination - to make it simple. One of those areas, for instance, concerns the meaning of sounds: if we look back in history, since the 50s “l’écoute réduite”, or reduced listening brought by Pierre Schaeffer (father of electroacoustic music), clearly aimed at putting aside the sound’s causal message in order to focus on its acoustic characteristics. It helped to create all kinds of new abstractions that could be used to compose music, without much focus on their meaning... or more precisely, deliberately without meaning.
This has changed the way people listened to sounds for decades, but still today very few have questioned the starting point there: what if we didn't remove the meaning but changed it, for instance? I find that many musicians rely on technology to find new sounds and new ways of composing, where very simple ideas could lead you to unknown territories. What if we included meaning again, or simply twisted it?
For most people a door is a door, a piano is a piano, an analog drum machine is an analog drum machine and footsteps in the snow are, well... footsteps in the snow. And silence is quieter than noise. Now what if I silence became louder than noise? Just invert the way a compressor usually works and get to work. What if we sculpted music out of white noise instead of adding instruments together? What if my footsteps in the snow were subtly mixed with an equatorial forest recording, how would you call that? And what if I just used lyrics to modify the perception of sounds/music, by inducing new meaning? Or what if I stated that a doppler effect will be my main instrument?
I once was asked to perform with a jazz/rock band, and told I could do whatever I wanted so I chose to play a duo with the leader (he was playing the saxophone with a lot of distortion), and played a reverb solo for 10 minutes with him. We got a standing ovation in the end, people had no clue a room could be an instrument! Another time I played the sea, some personal recordings split in narrow bands of frequencies with a whole system of sends that would allow me to perform music for hours without ever playing twice the same thing, etc etc.
Well enough of me talking about what I do (and sorry if those examples above go in way too many directions), but with a little bit of thinking you'll find out that much of the things we do seem unchangeable for some reason I can't yet figure out... because they are not! No doubt there is plenty of room for innovation, but it sounds to me that new technology is rarely the solution to it, basically because everybody is looking in the same direction while ignoring so much on the side. I mean, even in a technological direction (so I'll forget the meaning for now), look at Monome: the grid was a simple set of on/off buttons which didn't represent an evolution towards new technology . It couldn't create new sounds, nor any sounds on its own actually. Yet its beauty and simplicity led to a whole set of new ideas about how to compose, which is probably a good hint towards what I have been describing above.
Sorry for the long take, and thanks for the nice contributions above (I really am enjoying the Chris Cutler Probes series by the way)!