The switched PSU chirps

Graham, soaked the plus in isopropyl alcohol (IPA), worked first time.

ServerBaboon, the Mascot comes with 2 interchangable plugs, 2.1mm and 2.5mm. The 2.5mm is the size I am using.
The 2.1mm will not go into the socket (to small).

We have had some real difficulties making the green and 2007 models work the same, and we are still working on a model that will do both types of power supply. The 1k6 makes it better with our PSU1 power supply, but may make it less good with the SM-PS. You are free to try it, but be prepared to have to change it back. And also, please report your findings here.

Andy9672 wrote: Graham, Just reading this thread for the first time as my television (lcd flat screen) has started to chirp! lasts arround 7-10 secconds about every 30 seconds, only notice it now our baby has been born as we are turning it down more than usual! I know on our tv there is not a lot i can do but an idea came to mind that may help with your SMPS problem. How about an extention for the DC cable so that the power supply can be located furhter away from the listener? I also find with my mobile ohone charger that placing it on a granite drinks coaster helps a lot in the whine. I can see that we are going to have huge SMPS cases that are accoustically insulated. oh and i hate energy saving light bulbs, i thought we had left the dark ages!!

I second that last sentence...

I will look into the extension cords.

I keep 4 or 5 (one from each batch we bought) of the SMPS supplies permanently on within 1.5 metres of where I sit doing the office and design work at my computer and only really hear them when changing a connection on the equipment we have on test - when I'm within 0.5m of them, or in the "dead" of the night if I'm working very late/early - but I hear the computer and fridge more (the computer is one of those low noise HPs)

I never heard one chirp even after over a year of usage, but my situation may be a lot different to those who've heard chirping...

1] My electrical wiring is quite close to the consumer unit (in the same room)

2] I don't go via a mains cleaner/conditioner

3] They're hidden behind a cupboard

4] At 54 my high frequency hearing falls at 13kHz but as a child it was nearer 18kHz as I remember my physics teacher did an experiment on us.

Unfortunately the world is stuck with an ever growing emphasis on switched mode power supplies which are good from the point of view they save energy, but bad because of the downside of possible noise detection due to their untrasonic "mains" frequency, not forgeting their carbon footprint may actually be very similar to a linear because although they waste less energy, they take a lot more energy in manufacture because of the large number of parts they use.

Good call!