LMS_GetStreamStatus() - Does not work?

If I read the stream status of a stream that works with

LMS_GetStreamStatus(&m_stream_handle[i], &m_stream_status[i]));

This line

std::cout << "Stream " << i << ": Timestamp: " << m_stream_status[i].timestamp << std::endl;

produces output 0. However, using the meta data connected to the stream like

std::cout << "Stream " << i << ": Timestamp: " << m_stream_meta[i].timestamp << std::endl;

it seems to work as it outputs the timer which goes up by the buffer size of the stream. Why is that?

Here comes the declaration part.

lms_stream_t m_stream_handle[NUMBER_OF_CHANNELS];
lms_stream_status_t m_stream_status[NUMBER_OF_CHANNELS];
lms_stream_meta_t m_stream_meta[NUMBER_OF_CHANNELS];

LMS_GetStreamStatus returns 0.