I’m using DUNU Kima 2 IEMs (20 Ω, 108 dB/mW) with a USB-C DUNU DTC 80 dongle. The IEMs plug into the dongle’s 3.5 mm jack. I hear a faint, steady hiss when nothing is playing or when I listen at low volume. I’ve tried it on my iPhone, laptop, and desktop, and the hiss is there on all three. I’ve ordered an Apple USB-C to 3.5 mm dongle (China version) and a standard JCALLY JM6 (CX31993), but neither has arrived yet. Could the DTC 80’s separate MAX97220 amp chip be contributing to the hiss? Would a dongle without a separate amp chip, like the standard JM6, be quieter with the Kima 2, or does it mainly depend on the dongle’s output noise?   submitted by   /u/madloggan   to   r/iems [link]   [comments]