go to the VST connections window.

setup 4 mono inputs, connected to the 4 emu inputs.

choose your channel in cubase, select the input channel to the one the guitsr is plugged into - this should be a hi-z or you should be using a DI box.

press the monitor button on the channel. you should see sound on the meter and hear it, with latency.

if not, check your emu control panel, in devices...vs tmultitrack.

First off, the E-MU 0404 has line level inputs. You need a mic preamp and and/or a guitar preamp for proper use. All gain (volume) and signal routing is done in the PatchMix DSP application not with windows control panels. Read your manual...