[megabigeye]

Old thread but related question: the Dragonfly Red outputs 2.1v and I want to use 3.5mm to RCA L/R converter cable and connect it to a Monoprice Monolith 7x 200W speaker amp's L & R RCA inputs to drive some speakers. The Monoprice manual says:

Input Sensitivity for Full Rated Power
RCA Input: 1.49 Volts
XLR Input: 1.67 Volts

Is it ok to connect the 2.1v DF Red at full volume or should I try to keep it at 75% or less?

Should be okay. I believe those are the minimum voltages that are useable. RCA is usually ~2V and XLR is ~4V.