I have a cheap 3.5mm clip on microphone from amazon that is mouse quiet when plugged in directly to my sound card. I checked the levels and even used mic boost (then turned it off immediately). I've found that I get a lot of hiss and hum this way as well.
My plan is now to get a USB audio interface like this one and connect the microphone to it via an RCA converter cable. Will this setup fix the microphone volume problems?