Tektronix PRISM User Manual page 131

Application information
SILENCE. The signal is at or below the specified Silence Level for a time
exceeding the Duration for Silence setting.
DISABLED. Indicates that an audio bar is not active. This message is mainly
seen with a Dolby Digital source when a listening mode is selected with a
reduced number of channels.
AES V BIT. Indicates that the Validity bit is set high for one or more data
samples. In the AES/EBU standard, a set validity bit indicates that the sample
is not suitable for conversion to audio. By default, the level meter bars and
Lissajous display treat the affected samples as zero samples.
NO AUDIO. Indicates that an AES or embedded input has the Non audio
bit set.
NOT PRESENT. Indicates that an audio bar is not present in the current
audio input. This can be present if a Dolby Digital input has a coding mode
indicating a reduced number of channels.
PRISM Media Analysis Platform User Manual 109