What devices are you trying to send MIDI signals to using SQUID'S USB port? Is it a synth or drum machine that doesn't have a 5-pin MIDI port?
Generally speaking, SQUID's USB port is for sending MIDI and other data to a host computer only and will not directly connect to the USB input on other hardware.
If the hardware is especially designed to be a "USB Host", it will act like a computer and receive USB MIDI signals from Squid. Examples would be Squarp Hermod, 1010 Blackbox, iConnectivity Mio products, etc. It's a very new function for a lot of machines to be "USB Hosts" but it is slowly becoming a feature from certain manufacturers.