Was the hum mechanical noise or audible through headphones?

Well, thermal grease should do.

The 7815 and 7915 need to be heatsink insulated? Or do they work without insulation?

I had to file a bit of the standoffs in order for the 35.5mm cap to fit... not much change in sound, maybe cleaner bass.16x32mm would fit without any other squeeze in issues.

Ordered 3300uf Nichicon KA 35V 16x35.5mm will come back with the results. By measurement it seems to have 38mm of off the board. Including the board thickness so it will be a tight fit. Will put some isolation tape on top of the caps, maybe they'll fit.

Can you provide a link for 35V replacement capacitors? I prefer Nichicon KA series. What is the maximum diameter and height?

Can you provide the link for download please?

Well I changed the capacitor to 1nf as per Gustard's recommendation and no more random clicking. Thanks for the insight.

https://uk.farnell.com/kemet/c1206c102k5ractu/cap-1000pf-50v-10-x7r-1206/dp/1414710?st=1000pf This one should do. Edit: Added C0G / NP0 link as per Gustard's recommandation: https://uk.farnell.com/kemet/c1206c102j5gactu/cap-1000pf-50v-5-c0g-np0-1206/dp/1414709?st=1000pf%20capacitor

Can you provide the C209 Farnell UK code? That's where I source the parts. Or at least the smd cap size (eg 803 1206). Thanks.

Solving the problem with lip-sync delay in my case was easy, I switched the U16 to an USB 2.0 port. No more dropouts as well.

Try an USB 2.0 port. Uninstall driver first then install it again.

Nice measurements :) Thanks for the details but the facebook page seems a bit outdated. I'll scan the warranty card and email them. edit: no response so far. Anybody?

Hi all. Anybody knows how I can contact Gustard? My volume potentiometer has certain positions where (my guess) does not track properly and the relays are acting like crazy switching like 5 at a time. I need a new pot. Anybody else experiencing this issue?

1.61 NFB stable confirmed too. 1.77 sounds really better but left-right random switching makes me crazy... anybody from gustard reading this?