I am maintaining source code for a custom-built, Media Player that was developed years ago by previous developers from whom I have inherited source code several months ago. It’s a Windows Forms Desktop application written in C#. It is similar to other Media Players except that it does some extra stuff like it works with hardware such as Philips and Olympus foot pedals. You can use foot pedals to do actions such as play/pause, rewind, fast forward, etc. The application uses some open-source tools such as ffdshow, Haali Media Splitter also known as MatroskaSplitter and DirectShow.

The trouble I am having is when this Media Player plays an audio or video and if the computer is left unattended for some time, mostly locking the computer and coming back, say after 20 minutes (in which period the computer sleeps I guess), the video and audio wouldn’t work. All that is shown is a black screen (see below). Pressing play/pause, rewind, fast forward buttons do nothing.

Things I have already tried without success:

1. Uninstalled ffdshow and installed K-Lite codec instead which is a similar tool
2. Uninstalled ffdshow and installed LAV Filters which is a similar tool
3. Tried displaying the media file after the timeout to check if the application is still remembering the media file – yes it still knows
   the media file after the lapsed period

Did anyone have any similar experience? Also, any direction(s) that I can take to solve the issue would be highly appreciated.