Identifying and removing unknown Sound device
I also suffered from this problem after installing a software to use a wireless projector. Though the name is not ESHOW but DongleAudio in my case, I guess this works for you.


In Terminal.app, cd /Library/Audio/Plug-Ins/HAL
Remove the driver by rm -rf ESHOW.driver or rm -rf DongleAudio.driver
Reboot your Mac


I hope this helps.