Specify the exact name of your model, I see in the description of the G15 there is a Smart Amp, most likely this device is responsible for the distortion of the sound. In my case, the G814JV model, if I install the old version of the driver from zenbook (the laptop model is different, but in the contents of the inf I found a mention of my model), then the sound will be more from the left speaker, if the driver is newer, then from the right.
In the BIOS firmware, either intentionally or by mistake, the incorrect configurator 0409 was registered and the asus protection was triggered, which distorts the sound. I simply disabled the driver signature check and entered the lines of my device where 0409 = 0405 and the sound stopped distorting. Experiment with the audio drivers of the amplifier / realtek. Probably this inf is contained in Realtek.
