My SiriusXM (SXM) has a scratchiness in the volume control and in the sound. When I adjust the volume, either using the steering wheel control or the buttons on the main screen, there is a static, scratchiness sound like we used to get sometimes with analog volume controls where the resistive control sometimes corroded. I can move the control fast and slow, and the static always follows the speed. Also the scratchiness occurs when not adjusting the volume on the media content, but only on SXM. No other media source exhibits this static-type noise / distortion. Does anyone else have this issue or any suggestions as to the cause?