Phone using mobile data instead of Wi-Fi I installed Cyanogenmod on my HTC Desire about a month ago and have just received my first mobile bill. Before installing Cyanogenmod, I'd use maybe 200-300MB per month, because most places (home/work) I spend time have Wi-Fi that I can use. I have scheduled downloads of podcasts over Wi-Fi, configured to only use Wi-Fi (BeyondPod)... although I found that this setting had been unset when I changed from having 2 accounts on the phone (one Google Apps and one not) to just having 1 (Google Apps)... so I guess the preferences had been saved under the account I removed. 

Have had just received my first bill since I changed to Cyanogenmod and I've apparently used 4GB of data! That's going to cost me over $100 extra, so I'm not best pleased.

Some points/thoughts/questions...


I have Wi-Fi and mobile data enabled all the time.
Podcast downloads were scheduled for 4am so, even with the "only use Wi-Fi" option disabled, it should have downloaded over Wi-Fi at that time as I spend nearly every night at home and therefore on Wi-Fi
Sometimes when I unlock the phone, I see the mobile data symbol on screen briefly as well as the Wi-Fi one.
Is there a setting somewhere that is turning off Wi-Fi when the phone is locked? 
Is there a way I can prevent the phone from using mobile data when it's connected to Wi-Fi... and how do I make sure it's connected to Wi-Fi as much as possible?
Anyone got any tips/tricks to share for this scenario?
Go into the Wi-Fi settings, press Menu, choose Advanced. You should get options including Wi-Fi Sleep Policy. Sounds like its set to turn off Wi-Fi when the screen is off.