I’ve hooked a Douk Audio T8 Pro tube pre-amp/equalizer using the external loop on my receiver. According to my manual this should defeat the volume control/and bass, and treble on the receiver. The volume, and tone is supposed to be controlled at the T8 Pro. That isn’t the case. I have volume, and tone controls on both. Also when I use the external loop I loose around 10-12 clicks worth of volume. The output on the T8 Pro is rated at 1.2V RMS. Has anybody had a similar experience when using the external loop? I wasn’t expecting these results.