Dodgy speaker maybe?

Hi, I’ve just put together my picade, and stuck a Raspberry Pi 3 in it, running RetroPie.

So far so good. When I powered it on however there’s a really loud hiss from the right hand speaker, immediately on power on. I went through the recommended steps of adding the following to config.txt:

disable_audio_dither=1
max_usb_current=1

However the problem remains. The sound appears to be okay on the left hand speaker, although pretty quiet.

I checked the speaker connections to the picade board and they are fine.

If I increase the volume too much I lose the display as well. That’s with a 2.5A power supply.

The only solution I found was to disconnect the right hand speaker entirely, then it all works fine - albeit mono.

Does this sound like a dodgy speaker I have, or is there something else I haven’t tried?

Any advice appreciated!

Apart from this small teething problem, I’m delighted with my picade!

Hi GtB,
If you physically swap the speakers over do you get the same issue, with the right channel?
If you do this would then point to an issue with the picade board.

Mike.

Thanks for your reply Mike.

I tried swapping the speakers as you suggested, and noticed I’d screwed in the picade board a bit tight while I was doing it, it looked slightly bent. So I loosened it a bit when I swapped the speakers.

Turned on, and the whole thing works fine - both speakers working as expected, no hiss, and plenty volume.

If I crank the volume right up to the maximum, I still lose the display until I reduce the volume a couple of notches, I’m guessing I’m probably right on the edge of my PSU capabilities, running the Pi3, screen and picade all at the same time.

But I’m happy to plug in external powered speakers for those rare occasions when want to annoy the neighbours.

I don’t know if it was my shoddy wiring, or bending the board that was causing the issues, but it’s fixed now.

Many thanks for your help Mike, much appreciated!

Alan

No probs Alan, glad i was able to help

As for the volume issue it has been mentioned a couple of times by other people that the max volume on the picade causes too much draw on the power, and causes issues if the screen is also running off of a single 2.5a supply.

Mike

Hey so, this is happening to my speakers… do I have a dodgy picade board? I swapped speakers and the hiss is always on the right speaker panel on the board, no matter what speaker i have plugged into it. Please advise!

Hi Guys

One last thing to try would be a different audio cable just to make sure. but just as a precaution could you be able to take a picture of the audio input jack.

Thanks
Gee

Hi Moxie,

When I swapped the speakers around (to see if it was the speakers or the amp on the picade board), it appeared to solve the problem - so in my case it was probably a wiring problem.

I did notice though that I had screwed the picade board down quite tightly and it appeared to be under a bit of stress - in my cabinet it doesn’t quite lie flat, so was being twisted. So I also loosened off the screws slightly on the board, so that it wasn’t being stressed - that might also have been the reason the problem ‘fixed itself’.

I still get a slight bit of hiss if I push the volume up too high. I replaced the audio cable which improved it slightly, but it’s still there when the volume is over about 75%. My research suggests this is due to the audio out on the rpi3 being a bit ropey. Someone I know used a USB audio adaptor instead and got much better results.

Ok, swapped the speakers, swapped the cable positions (red to negative, black to pos), swapped a new 1/8" mini stereo cable (which used to transfer audio from raspberry pi to picade board)…

still get the fuzz, coming from anything plugged in the Right channel of the picade board. it seems connecting anything to the Right Channel negative port starts the fuzz/hiss.

Is this a bad picade board? :-(

Hey i also got big buzzing sound from the right speaker. However i testet a bit around, the sound from the Pi is not very loud and basicly bad. Testet the audio cable and picade board with smartphone and booth speakers are working.

On a side note i installed my screen upside down so the screen display board is not that stressed.
I think te buzzing comes from the HDMI cable.

Any suggestion to fix this problem ?

Hi

I had similar issues and my solution was to ensure there were none of the button wires anywhere near the corner of the PCB where the amplifier chip is (near the speaker connectors). I also replaced the audio cable with a shielded one and set the volume on the Pi to maximum.

Cheers

Paul

Yea I tried all of that and the fuzz and hiss are still there. Pimoroni crew, please advise… is this consistent behavior for a bad picade board?

Hi Moxie

Please would you be able to take a picture of the board close in as you can to the audio input socket I should be able to diagnose if there is an issue there straight away.

regards
Gee

Here’s some photos (i hope that helps):

Hi Moxie

Thanks for the photos. I can see a potential fault on the audio socket. If you could email support@pimoroni.com we will replace the board I’ll make sure it is one i have full tested myself. :) sorry about the troubles you’ve been having and we will get you up and running with your Picade.

Regards
Gee

Thanks @rabid_inventor! Just emailed them :-)

@rabid_inventor Out of interest, after looking on the pics, how you did figure out there is a potential fault on the audio socket ?

Just an update – I received the new picade board and it is working swimmingly! no hiss, no fuzz, nice and loud arcade sounds :-) Thank you!

And echoing @AndiBcool, how did you diagnose it so easily?

Hi Moxie and Andi

There is the potential for a poor solder joint on the audio input jack it is something we are taking care of in manufacture but very rarely a board can slip through.

I have marked the image where the issue is. It could be quiet easily sorted with a soldering iron and a touch of solder but we much prefer you to have a new shiny working board than asking you to fix it yourself. ;)

Once again sorry for the trouble this has caused

Regards
Gee

Oh i didnt realise i could enlarge the picture, but its only well noticeable on that pic.

By the way my speakers are still buzzing too.

i did try two different audio cables now, one is shielded and one is shielded even with ferrit on booth ends.
The game sound is hardly noticeable but i set sound in ES to over 90%. The buzzing becomes louder if i disconnect the cable from the pi.

I did look at the picade board but the contacts do not look that off like on Moxies board. However there is not much soldering fluid on the pins.
Taking pics was quite hard but i managed to make 2 good ones i guess.

.

Well testet still a bit picade board only, there is still buzzing when picade board is running alone and smartphone for sound conneted. when i increase sound to max on the smartphone the buzzing wount be that loud ( unless i increase sound with the buttons on the picade ). The buzzing also reduces when i touch the outer metal from the USB connector ( i use another cable to connect the USB Cable to the 5V power supply).
Tomorrow i will set up the pi with a USB soundcard and look how that work out.