Audioengine D1 Dac/amp (Price is firm) USB and optical in, RCA out. Working and in good condition. https://www.amazon.ca/Audioengine-D1-24-Bit-Computer-Interface/dp/B006IPH5H2/ref=sr_1_2?crid=2FEX51MR87WHO&dchild=1&keywords=audioengine+d1&qid=1591210559&sprefix=audioengine%2Caps%2C200&sr=8-2