Business households using balance fluctuation announcement speakers need to be vigilant against tactics that exploit these devices to commit fraud and appropriate assets.

Scammers create fake fanpages impersonating banks or speaker distributors to approach victims. When users request support for device setup or upgrades, they pose as technical staff, guide users to download unfamiliar applications, and demand personal information as well as Citizen Identity Card photos. From there, they seize control of the phone, steal OTP codes, and execute unauthorized transactions.

In another tactic, scammers use a phone to replay the "ting-ting" sound identical to that of a transfer announcement speaker. Taking advantage of crowded store hours, the suspect pretends to transfer money or overpay and then plays the pre-recorded successful transaction sound. If sellers only rely on the audio notification without verifying actual balance fluctuations, goods and money can be appropriated by fraudsters.

Bkav Cybersecurity experts recommend:

• Do not rely on sound to confirm money has been received. Always open banking apps/notifications and verify the account balance before handing over goods.

• Only purchase, set up, and repair "transfer speakers" through official channels of reputable providers.

• Do not provide OTP codes, identity card photos, or personal information, nor grant strangers remote access to your phone.

Bkav