Check your power supplies
With the New Year comes New Year Resolutions. The little 5V plug pack that came with the laser show Christmas Present was stamped with a working range of 100 – 240VAC, 50/60 Hz. It will work well in the USA on 110V and even in China where the mean voltage is 220VAC.
These devices list 240V as the maximum voltage, whereas in Australia the supply is typically 240V and often higher. Specifically, it is 230VAC -6%, +10%. This means that any mains supply within the range of 216V to 253VAC is deemed acceptable and cannot be reported as a fault.
A lot of these 240VAC Max supply units are quite stressed out on the VK power grid. It makes them prone to overheating, generating copious interference and internal breakdown of key components. All switch-mode power supplies imported to Australia should be rated to the 265VAC standard.
It is worthwhile to do the household rounds of all the little appliance plug packs that tend to choke our domestic power outlets and read the fine print on their voltage ratings. If any reveal a 240VAC maximum rating like the little one here, there is a good case for replacing it. Christmas should be celebrated without the odour of melting plastic and burned semiconductors.