How can I troubleshoot the cracking/beeping/fluttering/clicking/high pitched noise issue while using Preamplifier?

• All cables are securely in place and correctly connected.
• Test away any interference devices (e.g. wifi repeater, phone).
• Try different power supply and socket.
• If it has multiple input/output modes, try other modes to see if the issue persist.
• Check if the noise is still present when the input is disconnected.
• Try to connect it to different sources, output and cables. Try connecting to ground isolator.
• Test the turntable on another preamplifier to check if it has the same buzzing sound through the speakers. 
• If it is a tube preamp, re-seat the tubes, switch them, try a spare pair of tubes.
• Note: If phono preamp, replace high-quality well-shielded cable, the ground wire between the turntable and preamp is properly attached. Do not place your speakers on the same surface as your turntable.

If you have any questions or concerns, please don't hesitate to contact support@fosiaudio.com.