I am very new to this type of equipment so I apologize in advance for my lack of expertise in the sound arena. My situation is this. I have a live event coming up. I have an acoustic guitar connected to my Fender Acoustic 100w amp which allows for two inputs. I have my acoustic guitar connected to input 1 via 1/4 inch and I have a condenser mic connected to the TubePre v2 via XLR. I have the TubePre output connected to input 2 on the guitar amp via XLR as well. I have the drive and gain levels on the Tubepre at about 25%. I have the 48V Phantom power and 80hz options selected. I am able to play guitar and have singers sing into the mic with no issues at fairly low amp levels (3). If I try to bump up the volume on the amp for the vocals, I start to get noise. The setup seems very sensitive. Last year I had a dynamic microphone and had no issues and I had that input volume on the amp at 9 in order for folks in the hall to hear it. Now having a condenser mic with the Pretube, I would like to be able to increase the volume for the mic for the performance (doesnt need to be at 9) but want to eliminate any chance for noise or feedback during the performance. Any suggestions from the sound experts out there? Thank you so much for your time and assistance.