The effect of a so called "coupling factor", a, on the spectrum of a simple 2-D oscillator is investigated. An exact analytical solution for the spectrum of this oscillator is presented. We find that the position of the peak of the oscillator spectrum can be moved according to the value of a. Also, non-Lorentzian line shapes are shown to appear in the phase noise spectrum as a result of varying a. These phenomenon have not been described previously in the context of phase noise in oscillators. All results are verified by an experimental 2-D oscillator constructed using standard components.