|Microsoft DirectX 9.0|
The SeekDown method changes the channel to the next lower channel with valid programming.
This method takes no parameters.
When the method succeeds, it returns S_OK. Otherwise it returns an HRESULT error code.
This method returns immediately, and the seek continues in the background. The seek can be canceled by calling any other tuning operation.
Currently the DVB-C and DVB-S Network Provider filters do not implement this method, and return E_NOTIMPL. The method is implemented for DVB-T.