Firmware problem?

Hallo to all,

   recently i came across a very strange problem. After i upgraded my TV Live box with the latest firmware update some

   .avi and .mkv files cannot be played from the “ALL Video” option but if i go through the browser option then the files

   are played without any problem. Yesterday i had again this issue with a .avi file. Do you think that this is a firmware bug?

   Has anyone else had any similar problem ? Tonight i will have some more time in order to experiment some more and

   give more feedback.

Best regards to everybody and thank you for your time,