"I clicked Start Audio Engine and nothing happens"

Open the browser console. The most common cause is an AudioWorklet that failed to load — you'll see warnings like "Failed to load Acid-303 worklet." Hard reload the page; if it persists, check that your browser supports AudioWorklet (every modern browser does, but obscure WebViews sometimes don't).

"My MIDI keyboard isn't showing up"

Web MIDI requires HTTPS (or localhost). It's also unsupported in iOS Safari. On desktop: accept the MIDI permission prompt; if you missed it, open browser site settings and grant MIDI access manually.

"My kick drum sounds clicky / muffled"

Likely the granular path is engaged when you don't want it. Open the Sample Editor on the kick track and switch to ⇔ Varispeed. (Sonyk auto-bypasses granular at unity pitch, but if your pitch / fineTune / drift adds up to a non-zero shift the granular path takes over and can smear sharp transients.)

"Notes I tap aren't being recorded"

Either the transport is stopped and Step Rec is off (= practice mode, audition only), or the wrong track is selected. Press R to enable Step Rec, or press play first. Selected track is the one with the cyan border in the grid.

"Patterns drift out of sync after a few bars"

That's polymeter, not a bug — tracks with different step counts cycle on their own schedules and only re-align at the LCM of their lengths. If you want all tracks re-aligned every bar, set them all to the same step count (16 / 32 / 64).

"The share URL says 'too large to share'"

You probably loaded large user samples. The share format is gzipped JSON in the URL hash; big embedded WAVs blow past the limit. Use Save / Load to a file instead, or trim samples to shorter snippets before sharing.