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BAR48/Cinema 400 Subwoofer (8") No Power On (or no return from sleep) Possible Fix


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I have a CINEMA400 Soundbar from Klipsch. 
After a dust storm in my area (power started flickering due to the power wires flying around) the subwoofer decided to stay in this state where it wouldn't start for whatever reason. Sometimes it does, sometimes it doesn't. I figured I'd take what I know about electronics and try to fix it myself. 


Long story short, on the 3.3v rail, either the cap from factory isn't as good as it should be ( though I don't remember this happening before but it started happening more and more and I got annoyed since lately IT WAS turning on but today it wasn't and I wasn't going to wait for it to fix itself) or it's degraded pretty fast causing this issue from what I gather. 


The 3.3v cap is the one between (what I assume is) the wireless chip and the heatsink for the amp, it's labed 10v 100uf. 

This needs a little bit of spice, so I added another cap on the bottom, my cap is a random one I had in my bin (I like to remove capacitors from any PSUs/boards I am going to toss.. never know when you may need one) I don't recall the exact spec but I want to say it was a 16v cap, I will post back exactly what it was. 

During my measurements the voltage wasn't really moving but I thought to myself "what if I try holding another cap right under it to see if it works.. (taking note of polarity.) " and to my surprise it came to life.


In a completely unrelated post (even after I fixed it) I saw this: 

 (some guy saying an ic was causing something to go into protect due to the load) therefore it seems to be atleast on the same page of this.


I actually thought of trying this due to some issues in a network switch (netonix AC-8-150) which was solved on a 3.3v by adding a cap, to which again I had added a random cap from my cap stash and it worked and has been working for years.



The main and only symptom (other than it obviously not making bass) was that the blue light would flash for like a nanosecond every 2-3 seconds and not do anything else. Messing with the pair button (holding?) would make it go solid, but not work and no way to really pair it since I'd assume it wasn't doing anything.



Useful info for anyone working on one of these:

PSU seems to output around that of 32v when not underload/connected.

Here are some images of some of the chips on the PCB https://imgur.com/a/ki1kAwD I have yet to take the heatsink back off the amp to take a look at what that is incase anyone needs it (blown amp?) 

I believe that Wisyation WS9526DL is responsible for the wireless connection between the bar and the sub. (and maybe going in and out of sleep mode)

Meanwhile the ntp6810a I'm going to guess is probably doing some audio filtering (maybe LPF?)







tldr; if sub go nanosecondblink and no worky, maybe check 3.3v cap (10v100uf labeled by the amp) by adding a bigger cappy.

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