Extremely disappointed with Massdrop.
My O2+SDAC Amp/DAC stopped working after 5 months of purchase. The O2+SDAC still looks brand new since it just sits on my desk all the time. I tried to contact Massdrop about the warranty and they offer me to return to get a refund or to replace it with a new one but without a renewed warranty. When I asked for a refund, the customer service disappeared. I would not suggest buying any Massdrop product anymore.