A gas turbine engine system including a first combustor having a first fuel nozzle and a second combustor having a second fuel nozzle. The system further includes a first acoustic adjuster having a first drive coupled to a first piston with a first fuel orifice. The first piston is disposed along a first fuel passage leading to the first fuel nozzle of the first combustor. The system further includes a second acoustic adjuster having a second drive coupled to a second piston with a second fuel orifice. The second piston is disposed along a second fuel passage leading to the second fuel nozzle of the second combustor.