TOPIC:

The blue indicator light on my MiniDSP 2X4 HD goes on and off randomly. I have checked the power supply connector by moving it (this has no effect) and the voltage on the jack (it measures 12 volts and is stable). There is no regular pattern to the LED going on and off and it doesn't appear to get worse as the unit warms up. There is still a normal delay between plugging in the power supply jack and the LED (and audio) coming on. Can someone in support give me a schematic of this part of the circuit so that I can fix it myself (I am an Electronics Technician by trade)? It appears to be an intermittent electrical connection, but I need to investigate further. I did not buy the unit directly from a dealer, but from a famous auction site. The sound output is NOT affected. Thank you.

I opened up the enclosure to inspect the connections to the LED and the integrity of the solder joints on the series resistors (all OK). I connected a voltmeter to the LED pins and measured just over one volt. Furthermore, I then noticed that the voltage rose to about 2 volts and the LED turned on. I left it on my bench for about 15 minutes (with no external phono cables only the power supply lead) and the LED stayed lit. So, thinking that the problem had been solved, I put the PCB back into It's enclosure. I then put back the phono cables and for a while the LED was on. Then it turned off again and now remains off as I'm typing this forum post. The sound remains unaffected as before. Next I'm going to disconnect the phono cables and see if this has any effect. Maybe this is some kind of grounding problem or is related to static build up. I'm guessing this LED is driven from the XMOS chip. Is this correct?

Personally I find that blue LED is too bright! What I wouldn't give for a broken one!!... Joking but actually I have put a small piece of black electrical tape over mine.

Maybe your LED is just a dud.

Hello Devteam,
Could you please give me the part number of the blue LED please? You can send me the part number to my home email address if you want. Hope you can help. Thanks.

David.

PS I also have an intermittent input on one channel. Do you have a snippet of the schematic for the 2x4HD that shows the connections for the INPUTS and the circuit surrounding the LED. I may have to do some reverse engineering in order to fix the problem and tell everyone about it in a YouTube video. Hope you can help.