Fosi Audio P1, User Manual, Page: 6 / 12

Troubleshooting/QA
1: Cables are connected, but no sound output?
• Check the POWER indicator is on, press the POWER button if the
light is still off, At this point, you can find the same output voltage
power supply (must 12V) to check if the machine or power supply
failure. If the POWER indicator light is on, check whether the
corresponding input signal is selected correctly.
• If the indicator light is on, check whether the VOL knob is in the
minimum position. If so, turn clockwise to normal Volume.
• Check whether the two vacuum tubes are fully inserted into the
jack.
• If both of the above are normal, check the input device if it is
paused, mute, or the volume is minimized.
Note: Make sure that all the cables are completely pushed into the
device.
2: Why does the sound is cracking?
• This product is for the tube preamp but also can be used as a
preamp, If post equipment is maxed volume & preamp too, it's
easy to distort, you just need to turn down the volume of the
equipment, then ok.
3: Why does the volume of the machine stay the same,
while the sound of different audio sources (such as CDS
and mobile phones) is different?
• The output range of different types of audio source devices is
different, the mobile phone is usually 0.35mV, and the CD is
1V.The signal output amplitude of the sound source will directly
influence the volume.