Audio is not clear

I have my Pi running into a USB sound interface card, amazon.co.uk/Behringer-UFO20 … B002GHBYZ0, then into a oldish Pioneer amplifier via the phono sockets. When I play music back it sounds really distorted and not clear like it should be. Any ideas on what I am doing wrong, am I asking too much of the Pi?

It’s always the same problem : usb power is crapy and the RPI does not provide much power. The best way is to have a DAC externally powered.

Is there any DAC’s that you suggest?

Your problem is not DAC or USB related.

Don’t plug line level audio into phono input !

The phono input have 2 amplifier stage, that’s why the sound is distored.

Sorry I don’t follow you. How would you connect up the RPI to an amplifier?

Like Elpy was saying, the rca jacks labeled “Phono” are reserved for direct connection to a turntable. Old amplifiers have phono preamps built in which makes this connection very different from the standard line level. It amplifies the low signal of the record player and applies equalization.

You would want to connect the dac/usb sound card to another set of rca jacks like one maybe labeled “Aux” or “tuner” or if not that super old “CD”.

You might already be doing this and just referring to the rca jacks as phono jacks. If that’s the case, I guess it could be your rpi/dac set up which would make it a little more difficult to troubleshoot.