I currently have an old O2+ODAC combo device which has pre-amplified RCA outputs at the back. I use it to drive my Genelec 8020B speakers and various headphones. So far I've been really satisfied with it, but now I'm looking for something new that also has balanced XLR output for headphones and can still drive my speakers, preferably with an output switch. I would prefer a combo device but stacks are fine too. My budget is around 300 dollars, what is the best I can get with this money?