starting WLAN to slow - no NAS mount

Hello together,
i have the following problem:
Raspberry Pi 2 B, Hifiberry Digi+, Volumio 0.979

When i run the pi with LAN-Cabel everthing is fine.
Only with a edimax wlan stick volumio can´t mount the nas cfis-share. When booting volumio is try´s to mount the share, but the edimax wlan isn´t connected to the network at this time. Volumi show mount error on the screen an a few second later the edimax is connectoe to network.
So i think there is a time problem, the mount of the share has to wait until the pi is connected to the network.

Is this a known bug?

Thank´s and best regard.
Highender