Main monitor loses native resolution when extending using HDMI switch
Hi,
I have a late 2009 iMac 27" running OS 10.9.5. I extend the desktop to a projector using a MiniDP to HDMI adapter, that works great. I recently added a HDMI switch for displaying multiple sources on the projector. The switch changes the resolution on my iMac's main screen, even though system preferences still shows the setting to be at native resolution. When I power on the switch the resolution drops, cut the power and it goes back to normal.
Is there a way to stop this happening? I've tried SwitchResX and it doesn't help.
Thanks,
-HS
iMac, OS X Mavericks (10.9.5)