I had issue with mic input in my lenovo legion y520, the mic is picking up output sound , and static sound , and mic is too quiet , i thought it was the 3.5mm jack problem , but after i use the usb headset (msi gh70) the problem still same , i've been searching from internet for the solution , and nothing work
I just realize , if i use separate mic or headphone , the mic normal , but when i use the mic built in the headset , the problem still occur
USB driven headsets and analog 3.5mm driven headsets are two worlds primarily due to the fact that the analog headset will be powered by the onboard audio chip while the USB headset will have all the audio processing taking place at the USB port. See if you have any BIOS updates pending. After that checks out, uninstall and reinstall your onboard audio drivers(Realtek) with the latest found off of Lenovo's support site and try your analog headset.
Speaking of headsets, please pass on the make and model of both headsets. If you can't identify them, a link to them would help us two fold.