Sorry, but updating to 4.8.0-30-generic yesterday still didn't solve that problem for me.
In my case it is the USB speaker (Alesis M1 Active 320 USB, which works as external sound card) what causes all USB ports except one to disconnect after playing sound for some seconds.
Luckily I can have my mouse at that remaining USB port.
Since 16.10 the only working kernel for me is 4.7.0-040700-generic.
Sorry, but updating to 4.8.0-30-generic yesterday still didn't solve that problem for me.
In my case it is the USB speaker (Alesis M1 Active 320 USB, which works as external sound card) what causes all USB ports except one to disconnect after playing sound for some seconds.
Luckily I can have my mouse at that remaining USB port.
Since 16.10 the only working kernel for me is 4.7.0-040700- generic.
Will I have to wait for 4.9?