This should play if your Web browser has WebAssembly enabled (most do). Most examples will play unless they need to load files. The first time you click Play, Csound will spend a few seconds loading, then play. You can edit this code and replay it.
<CsoundSynthesizer> <CsOptions> -odac </CsOptions> <CsInstruments> ; Required settings for WebAudio: sr = 48000 ksmps = 128 nchnls = 2 nchnls_i = 1 ; nchnls = 2 0dbfs = 1 ; ksmps = 128 ; sr = 44100 instr 1 isize init 1024 ioverlaps init 4 asig diskin2 "fox.wav", 1, 0, 1 kframe[] framebuffer asig, isize kwindowedFrame[] window kframe, isize aout olabuffer kwindowedFrame, ioverlaps aout = aout / 2 outs aout, aout endin </CsInstruments> <CsScore> i 1 0 400 </CsScore> </CsoundSynthesizer>