Orca volume at logon is too low

[Cleverson Casarin Uliana]

Hi, please how can I raise the volume for Orca during the logon screen? 
It's too low.

I don't recall what desktop manager I'm using to log on, but it's the 
same installed with mate by default on a new installation.

As soon as I log on, the volume gets loud enough.

thanks,
Cleverson