@chmaruni in case anybody else has this problem: I upgraded everything, including upgrading the distro from Jessie to Stretch, then upgraded all the retropie modules, and then (and that was important) I deleted the sdl-vicerc config file. After that, sound and joysticks are working again. Deleting the config without the distro upgrade didn't work for me. Anyhow, seems to be working again.
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