UserAgent: Mozilla/5.0 (X11; CrOS x86_64 9202.18.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/57.0.2987.32 Safari/537.36
Platform: Platform 9202.18.0 (Official Build) beta-channel monroe Firmware Google_Monroe.4921.17.0

Steps to reproduce the problem:
1. Power on LG Chromebase
2. Login to owner account
3. Plug in USB Flash, External SD card, External CD/DVD/BD USB drive

What is the expected behavior?
USB storage devices mounted as usual in "Files" application.

What went wrong?
USB storage devices are not recognised and they can not working.

Did this work before? Yes 56.0.2924.87

Chrome version: 57.0.2987.32  Channel: beta
OS Version: 9202.18.0
Flash Version: 24.0.0.221 /opt/google/chrome/pepper/libpepflashplayer.so

I was using my LG Chromebase with different USB devices alote.
Before major upgrade to M57 all my devices works fine.
After upgrade to M57 only part of my devices works fine e.g. USB mouse, USB keyboard, Extarnal USB speakers, External USB mic, External USB Webcam. No one USB mass storage devices are working now e.g. USB Flash, External SD card, External CD/DVD/BD USB drive.