A 55-year-old male underwent combined coronary artery bypass grafting and mitral valve replacement with a No. 31 St. Jude Medical mechanical prosthetic valve. Over the next few months, the patient experienced severe difficulty with the 'clicking' noise of the mechanical valve, to the extent that it affected his daily activities. At approximately four months after the first operation, and at the patient's insistence, he underwent redo sternotomy and replacement of the mechanical mitral valve with a Mosaic porcine bio-prosthesis, with an uneventful recovery. While this case represents an unusual indication for valve replacement, it illustrates the importance of considering non-traditional factors when choosing the optimal prosthetic valve.