The PT2258 has 6 (3 stereo) seperate channels and seperate outputs.
So I could use resistors at the output and connect them all together.
Will those resistors have influence on the high frequencies, or is this very low with metalfilm resistors ?
The resistors connected together reduces also the signal, so I have to amplify it.
If I have to filter the 5V, it could be a little below the minimum of 5.0V, so I might also need an extra power circuit for it.
Is there something simpler, like a complete digital mixer in one chip ?