Gaming Equipment Abnormal Behavior: Signs, Causes, and Solutions
“Abnormal behavior” is the catch-all term operators use when a machine is doing something it should not — but they cannot pinpoint exactly what. The machine acts strangely, produces inconsistent results, or just “seems off.” This vagueness makes diagnosis difficult, which is why many operators tolerate abnormal behavior until a major failure forces action. This guide turns vague “abnormal behavior” into specific, diagnosable categories so you can identify the cause and apply the correct solution.
Category 1: Electronic Abnormal Behavior
Symptoms: Machine randomly adds credits without bill insertion. Payout triggers without a winning game. Game outcomes change midway through display. Bonus rounds trigger when conditions are not met. The machine responds to commands that were not input by the player.
Cause: Wireless signal injection on the communication bus. An attacker near the machine is transmitting signals that the bus interprets as commands.
Confirmation: Observe: do the abnormal behaviors stop when the attacker leaves? If you have bus monitors, check the device log — blocked attack signals confirm electronic interference.
Solution: Install bus monitoring devices on all machines. The devices block unknown signals. The abnormal behaviors stop because the signals causing them are blocked.
Category 2: Mechanical Abnormal Behavior
Symptoms: Bill validator rejects bills that are clean and undamaged (intermittent). Coin mechanism jams frequently. Hopper dispenses the wrong amount or jams. Buttons stick or do not register presses. Touchscreen has dead zones or ghost touches.
Cause: Mechanical wear, dirt accumulation, or component misalignment. Mechanical parts have finite lifespans.
Confirmation: Test each peripheral individually. Bill validator: run 20 bills through. Coin mechanism: run 50 coins through. Buttons: press each 50 times. Hopper: trigger 5 payouts. Count failures. More than 5% failure rate = component fault.
Solution: Clean first (compressed air, contact cleaner). If cleaning does not resolve: recalibrate (bill validators and coin mechanisms have calibration routines). If recalibration does not resolve: replace the component.
Category 3: Software Abnormal Behavior
Symptoms: Machine freezes during gameplay (requires restart). Game displays graphical glitches (sprites missing, colors wrong). Game logic breaks (impossible outcomes, wrong paytable values applied). Machine reboots spontaneously.
Cause: Software bug, corrupted game data, or failing memory that causes data corruption.
Confirmation: Record the behavior on video if possible (helps manufacturer diagnose). Check: does it happen on specific game actions or randomly? Is it reproducible (same action always causes it) or random? Does the machine record error codes in its log?
Solution: Update firmware to latest version (many bugs are fixed in newer firmware). If firmware is current and the problem persists: clear and reload game data (corrupted data is cleared). If problem still persists: replace the mainboard (memory failure on the mainboard causes data corruption).
Category 4: Configuration Abnormal Behavior
Symptoms: Payouts are larger or smaller than expected. Game difficulty seems different (too hard or too easy). Features that should be available are missing. Machine displays menu items that should be hidden.
Cause: Configuration settings changed (accidentally or intentionally).
Confirmation: Compare current configuration to baseline. Any differences are the cause of the abnormal behavior.
Solution: Restore baseline configuration. Document the change (who, when, why). If change was unauthorized, investigate and change configuration PIN.
Category 5: Environmental Abnormal Behavior
Symptoms: Machine behaves normally in the morning but abnormally in the afternoon. Machine behavior changes on hot days vs cool days. Machine near a specific wall or fixture behaves differently from identical machines elsewhere.
Cause: Environmental factors: temperature (electronics behave differently at temperature extremes), humidity (condensation on circuit boards), sunlight (display glare affects touchscreen sensitivity, heat affects bill validator sensors), power quality (voltage fluctuations cause erratic behavior), and vibration (nearby machinery or heavy foot traffic causes connections to loosen).
Confirmation: Measure the environment: temperature at the machine location (morning, afternoon, evening), humidity, sunlight exposure, and power quality (voltage monitor). Compare the affected machine’s environment to a normally-behaving machine. Also try: swap the affected machine’s position with a normally-behaving machine. If the abnormal behavior stays with the location (affected machine becomes normal in new location, previously-normal machine becomes abnormal), the environment is the cause.
Solution: Mitigate the environmental factor: air conditioning or fans (temperature), dehumidifier (humidity), window blinds or machine repositioning (sunlight), power conditioner or UPS (power quality), and vibration isolation pads (vibration).
Diagnostic Framework
When a machine shows abnormal behavior, ask these questions to categorize it:
- Is the behavior random or patterned? Random = electronic interference or software bug. Patterned (same time, same action) = mechanical wear, configuration error, or environmental factor.
- Does the behavior affect one function or multiple functions? One function (bill validator only) = specific component fault. Multiple functions (credits, payouts, display) = electronic interference or mainboard failure.
- Does the behavior stop when specific conditions change? Stops when a specific player leaves = electronic cheating. Stops when temperature drops = environmental. Stops after a restart = software. Never stops = hardware or configuration.
- Have other machines of the same model shown similar behavior? Yes = software bug (report to manufacturer) or batch hardware defect. No = this machine has a unique problem.
Answer these four questions. The answers will point to one of the five categories above. Apply the corresponding solution.
Our guide includes an abnormal behavior diagnostic flowchart.
Common Questions
What if the abnormal behavior is intermittent and I cannot reproduce it?
Install a camera focused on the machine. Record continuously (or motion-triggered). Review footage when the behavior is reported. The recording captures the behavior even if you are not present. Also: check the machine’s error log — many abnormal behaviors are logged even if the behavior itself is transient.
How urgent is abnormal behavior?
Electronic abnormal behavior (Category 1): urgent — every incident costs money. Deploy bus monitors immediately. Mechanical (Category 2): moderate — fix within days to prevent worsening and revenue loss. Software (Category 3): variable — data corruption (urgent, could worsen), cosmetic glitches (low urgency). Configuration (Category 4): urgent if revenue-affecting settings are wrong. Environmental (Category 5): moderate — get the mitigation in place before extreme weather hits.
Can abnormal behavior be a sign of tampering rather than cheating?
Yes. A machine that behaves differently than baseline may have been physically tampered with (component replaced, firmware modified). If the behavior cannot be explained by any of the five categories above: open the cabinet and inspect for unauthorized components, perform firmware checksum verification, and check for any anomalous entries in the maintenance log.
Abnormal Behavior Has a Cause. Find It.
“Abnormal behavior” is not a diagnosis — it is a symptom. Categorize the behavior using the five categories. Diagnose using the four questions. Apply the category-specific solution. The machine will return to normal operation. If you cannot categorize the behavior after this process, contact the machine manufacturer with a detailed description and video — they can identify software bugs and hardware defects you cannot.