My Lenovo also has this issue, but PJSingh5000's workaround in post#17 (https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1729389/comments/17) worked for me.
My Lenovo also has this issue, but PJSingh5000's workaround in post#17 (https:/ /bugs.launchpad .net/ubuntu/ +source/ linux/+ bug/1729389/ comments/ 17) worked for me.