I'm not sure if this belongs here, so move it if I'm in the wrong place. I just got done moving into my dorm a couple of days ago. I'm using a Pocket Rockit headphone amp for practicing. I brought up two basses with me. The first one is my Ibanez BTB400. The other one is an Essex fretless jazz. Everything was working great until last night when my Ibanez started sounding very distorted and quiet in the clean mode of the amp. I tried the fretless to make sure it wasn't the headphone amp and it worked just fine. I just replaced the batteries in the Ibanez, so I know that's not the issue. I think it might be my connection. It may also be something to do with my mid knob(s), which up until 10 minutes ago had always been a bit loose. I'm at a complete loss as to what to do. Please help me.