When connecting both USB and AUX cables to your computer simultaneously, it can lead to a ground loop effect, causing unwanted noise in your audio playback. To avoid this issue, it's advisable to use only the USB cable for audio playback. If you need to use the 3.5mm audio cable, ensure your speaker is powered by a USB adapter or another USB-powered device.
Additionally, when inserting or removing the 3.5mm jack, a static noise will occur due to minor electrical potential differences. This occurrence is for 3.5mm audio jacks and will not disrupt normal operation.