FB 7390: new firmware v05.51

I've the new firmware installed on my FB7390. New version number is 05.51.
The following error (popup) occured when trying to restart Homeseer:
3-4-2013 22:25:43
De index ligt buiten de matrixgrenzen.
HomeSeer version: 2.5.0.79
Source: HSPI_FBF
Target: System.String AccessMethod()
Stack trace:
bij HSPI_FBF.FritzBox.AccessMethod()
bij HSPI_FBF.FritzBox.GetPrefixes()
bij HSPI_FBF.FritzBox..ctor(String IP, String password)
bij HSPI_FBF.HSPI.GetFBInfo()
bij System.Threading.ThreadHelper.ThreadStart_Context(Object state)
bij System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
bij System.Threading.ThreadHelper.ThreadStart()
All entries on the Fritzbox are still the same, also the login password.
Reboot of the pc isn't a solve.
Further progress of the HS startup procedure was terminated.
edit: No need to go back to previous FB firmware. For the time being I renamed the "HSPI_FBF.dll" file, so the plugin is not started.
The following error (popup) occured when trying to restart Homeseer:
3-4-2013 22:25:43
De index ligt buiten de matrixgrenzen.
HomeSeer version: 2.5.0.79
Source: HSPI_FBF
Target: System.String AccessMethod()
Stack trace:
bij HSPI_FBF.FritzBox.AccessMethod()
bij HSPI_FBF.FritzBox.GetPrefixes()
bij HSPI_FBF.FritzBox..ctor(String IP, String password)
bij HSPI_FBF.HSPI.GetFBInfo()
bij System.Threading.ThreadHelper.ThreadStart_Context(Object state)
bij System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
bij System.Threading.ThreadHelper.ThreadStart()
All entries on the Fritzbox are still the same, also the login password.
Reboot of the pc isn't a solve.
Further progress of the HS startup procedure was terminated.
edit: No need to go back to previous FB firmware. For the time being I renamed the "HSPI_FBF.dll" file, so the plugin is not started.