Regarding KSFO feeds - KSFO Tower has some bad static and at times the Tower itself cannot be heard, only aircraft. It sometimes cuts off the Tower operator in mid-sentence. Similar problem with KSFO Class B feed and KSFO NORCAL Departture feed. KSFO Ground, however, sounds fine. Anyone else noticed this? It began about a week ago. Sunspots? Canadian Geese?