Hi from France, i just wanted to share my experience with the Topping PA 5.
I bought it around november 2022 and i have been using it since then. I bought it after reading your article. Thank you
I had big crackles in left channel in 2023, after 3 months of use. I tried to find a solution myself, filtering AC, with some Ifi products and with many other, and it worked very well until now. No more crackle. I bought a cheap android tv for streaming with UAPP on Qobuz cutting off the wifi, and trying to have the little possible bluetooth devices around. I also find that putting up the volume on the amp diminish crackles. I think it come from the ultra sensitive Topping PA5 catching all electromagnetic waves of my populated neighborhood and my own house.
It works very well and i can enjoy again my Hifi setup without crackles in left channel right now. Thank you for reading my english.