The Bastl DUDE seems to be generating interest, but what about the PBMIX3 portable mixer from the patchblocks guys? Due to ship in May '17 : r/synthesizers
Ripcord USB to 9V DC power cable compatible with the Bastl Dude Mixer
Bastl Instruments Bestie, portable 5-channel stereo mixer with feedback
BASTL Instruments Dude Mixer 2018 | Reverb
Is this TINY MIXER perfect for SYNTHS? First Look at BASTL DUDE - YouTube
MyVolts 9V Power Supply Adaptor Compatible with/Replacement for Bastl Dude Mixer - US Plug - Amazon.com