Fix flickering in Boxee with ATI graphics card

I recently installed Boxee on a new computer I got for my daughter.  It was running Ubuntu 11.04 and I used this fix to get it to install.  Unfortunately, like many in the comments section of the fix blog post, was getting too much flickering in the application to be able to use it.  It took me a little Googling, but I finally found a fix after following a link that suggested I follow another link, which finally took me to instructions that hinted at how to fix it.  Apparently the problem exists when using an ATI card with the open source driver and Compiz enabled, but don't quote me on that.

To fix it, one simply needs to turn off vsync.  To do this open up the guisettings.xml configuration file and change vsync from 2 to 0.

First, lets backup the file.

cp ~/.boxee/UserData/guisettings.xml ~/.boxee/UserData/guisettings.xml.bak

Now we need to edit the file.  Run the first command to do it with a GUI, or the second to use vim.

gedit ~/.boxee/UserData/guisettings.xml
vi ~/.boxee/UserData/guisettings.xml

Find vsync in this file and change the 2 to a 0, and save the file.  It should be line 551 in the file.  Lines 546  through 552 should look like this initially.   

    <videoscreen>
        <guicalibration></guicalibration>
        <resolution>11</resolution>
        <testpattern></testpattern>
        <testresolution></testresolution>
        <vsync>2</vsync>
    </videoscreen>

After the change they should look like this.

    <videoscreen>
        <guicalibration></guicalibration>
        <resolution>11</resolution>
        <testpattern></testpattern>
        <testresolution></testresolution>
        <vsync>0</vsync>
    </videoscreen>

Now if you start boxee it no longer flicker.