What I Did
A PoC for a Web Audio Player using client-side decoding to circumvent the codec-issues with browsers (mainly the absence of Flac decoders). I implemented both client and server using Aurora.js and Flac.js.
Yep, it turns out that there are some problems doing this (crackling, stuttering, jitter, low priority in background tabs → major stutter) that are not easily solved. Playing in a foreground tab without touching the mouse or keyboard worked pretty well though :-)
Most browsers support FLAC.