Not sure it's a bug - I had the same problem and solved it by installing
libsdl1.2debian-pulseaudio
This removes libsdl1.2debian-alsa, but after that I had sound on kdenlive again with pulseaudio selected as audio-driver.
Not sure it's a bug - I had the same problem and solved it by installing
libsdl1. 2debian- pulseaudio
This removes libsdl1. 2debian- alsa, but after that I had sound on kdenlive again with pulseaudio selected as audio-driver.