I had a similar issue and it was an interoperability problem with Cisco's power save mode (U-APSD/PS-Poll) and the Ruckus AP.
If you turn off the power save option on the Cisco handset, the issue with one way audio and dropped calls is resolved. Phones will drain their battery faster however.
More info on my blog - "One Way Audio on Cisco 7925G Wireless Phones"
http://networkcanuck.com/2013/10/04/v...
I hope this resolves your issue as well.