Why is my office intercom making a constant buzzing sound?

A constant buzz often indicates a ground loop, power supply problem, or electrical interference. The issue may stem from multiple grounding paths, failing transformers, or nearby electrical equipment generating unwanted noise.

Can electrical equipment cause intercom interference?

Yes. HVAC systems, lift motors, switchboards, variable-speed drives, and other high-power equipment can generate electromagnetic interference that affects communication circuits, causing buzzing or static.

What is a ground loop in an intercom system?

A ground loop occurs when equipment has multiple grounding paths that create slight voltage differences. These differences allow unwanted current flow, producing a persistent humming sound.

Why does the buzzing happen when someone unlocks the door?

Door strikes, magnetic locks, relay modules, and shared power circuits can introduce electrical noise when activated. This often causes buzzing that appears only during door release events.

Should I repair or replace an old commercial intercom?

If the system frequently requires repeated service visits, replacement may be more cost-effective than ongoing repairs. Modern IP systems often provide better reliability and functionality.