Shown here are the symptoms for common problem three. The engineer observes large varying offset voltages at the input pins especially with long winding leads in noisy environments. Noisy environments include next to an MP3 player smart phone or other high RF emitting device. The cause for this problem is that the long leads connected at the inputs act like radio frequency antennas and rectify the AC RF signal into low frequency near DC signals at the amplifier’s inputs, which no doubt is causing the noticeable errors at the output.