changing style causes ParserError

Question

When i try to change the style of my SMFPlayer at runtime it throws this error

Error: Unhandled Error in Silverlight Application Code: 2531
Category: ParserError
Message: Failed to assign to property 'Microsoft.SilverlightMediaFramework.Core.BitrateGraphControl.AvailableBitrates'.

the only change i made in the style was changing the color so im not sure how this affects it, but heres the code to change the style

if (_fullScreen)
            {
                this.Style = Application.Current.Resources["fullscreen"] as Style;
            }
            else
            {
                this.Style = Application.Current.Resources["preview"] as Style;
            }