This kind of sound usually does not come from inside the processor or the program, but is caused by a physical mechanism. The only moving part of your external processor is the coil cable, which is handled every single day, at least twice, morning and night. The plastic sheeting of the cord, which holds delicate wires connecting the processor with the transmitting coil can suffer wear and over time can tear the wires sending sound intermittently, causing a sensation of static or crackling. Talking about 'static' .....please be careful over winter when our synthetic jackets and jumpers, combined with wind and our rubber soled shoes, result in more static electricity being stored on our bodies than usual. Although the processors and the implants have clever electrostatic barriers, a strong static discharge directly on the processor or coil/ cable can corrupt (disrupt or erase) a program. Instruct your family to touch your shoulder before touching the processor, and always remove the processor before removing clothing over your head.