Hi. I bought SP4 i5, 128GB this week. I noticed soon a problem with my new device. It makes some annoying noise under certain CPU load. It seems that is it caused by voltage regulators or some other HW structure. It is NOT caused by fan. It happens even when the fan is off. The device makes sound only when it oriented in portrait mode with USB and power connectors on the bottom. I recorded the sound. Does anyone have similar troubles with SP4?