Topic: Signal pumping at fs/4 using two ADI-2 Pro FS & two PC's
Testing some jitter related using two ADI-2 Pro FS with to PC's.
Issue: Signal pumping on the ADC input level display using signal exactly at fs/4.
. Using latest firmware and swapped the DAC ADI and ADC ADI gear and getting equal results.
. The DAC / ADC is set at 19dBu. Int Clock source.
. The source signal is at -6dBFS
. SR on both gear with 44.1 kHz or 48kHz
. Connect both with a symmetric cable
. Feed out the signal and input of the ADC input level alters from -6.1 dB to -8.2dB (alters/pumping) within some seconds
. Recorded signal shows equal level pumping too
BUT: As soon I set the signal frequency different to fs/4 the pumping stops.
Is this know?