2. Whether users can upgrade M3 to the latest firmare skipping the medial version?

A: Firstly, you can check the firmware version on the M3 by "System settings" -> "About M3" (or Player information) -> "FW xxx".

When the M3's firmware is FW1.4/1.5/1.6, you can NOT upgrade the M3 to FW2.0 directly. 
Kindly be noted that, the firmware 1.4/1.5/1.6 has only 1 theme, then there are 2 kinds of themes from firmware 1.7, and 3 kinds of themes for the new firmware 2.0.
At present, the M3 can not be upgraded from the firmware which has 1 theme to the one with 3 themes.  If you upgrade the M3 from firmware 1.4/1.5/1.6 to FW2.0 directly, the M3 will be frozen, then you have to send the M3 to us to fix it!

That is to say, when your M3 is still running FW1.4/1.5/1.6, please try to upgrade the M3 to FW1.7 or FW1.9 firstly, then upgrade it to FW2.0.  If it is already FW1.7, then you can upgrade the M3 to FW2.0 by skipping the firmware 1.9.

FW 1.4/1.5/1.6 —>FW 1.7/1.9 —> FW2.0      √
FW1.7/1.9 —> FW2.0                                       √

FW 1.4/1.5/1.6  —> FW2.0                                X

Here is the new firmware 2.0 for the M3: 
click here to download, and the new features and improvements for M3 are as follows:

1. Added a new black UI theme (theme 3);

2. Added option to play songs through folders (can be set in System settings -> Play through folders)

3. The original "Restore factory defaults" and "Firmware update" are merged into "Other options" under "System setting".

P.S. here is the firmware for the FW 1.9click to download.

If the M3 is frozen(might be just stuck at 10%) when you try to upgrade it, please read this post carefully: click here