Make sure to install Line 6 Monkey as well as the drivers for your operating system before trying to connect the UX2. They are both available for free download from our software page below:
After successfully installing Line 6 Monkey and the drivers please try removing any additional unnecessary USB and firmware devices from your computer when troubleshooting this issue. Make sure to connect it directly to a USB port and not a USB hub, extension, or keyboard of any kind, preferably connect it to a USB port on the rear of computer. Try using additional USB cables and every USB port available.
Launch Line 6 Monkey and apply any updates that are available.
From here, you need to launch the Line 6 AUDIO-MIDI device menu located in windows on the control panel, and in mac on the system preferences.
Select the Inputs & Recording tab, and make sure that you have the correct input source selected. Connect your guitar or microphone to the proper input. If you are using a condenser microphone, make sure to engage the +48V phantom power. Then make sure to connect headphones or speakers to the Outputs on the UX2 so that you may monitor playback.