0

Music Maker shield hissing sound
Moderators: adafruit_support_bill, adafruit

Please be positive and constructive with your questions and comments.

Music Maker shield hissing sound

by Corker on Wed Jul 28, 2021 9:49 am

Hello,

I have purchased two "Music Maker" shields (PID 1788) and both have come down with the same problem - they produce a hissing sound when powered on. I have been using them with a couple Arduino Uno boards to play MP3s using 4 ohm speakers (PID 1314). Everything is powered from the PowerBoost 1000 (PID 2465) using a 2500mAh battery (PID 328). It appears that this issue has come up before from what I found on the forum:
https://forums.adafruit.com/viewtopic.php?f=8&t=99199&p=497137&hilit=1788#p497137

Were you able to determine what causes this problem? I really like the Music Maker shield but can't use them with the continual hissing sound.

Thank you.

Corker
 
Posts: 4
Joined: Thu Apr 20, 2017 11:31 pm

Re: Music Maker shield hissing sound

by mikeysklar on Thu Jul 29, 2021 5:12 pm

@Corker,

Are you able to try the volume suggestion from the forum thread you linked to. Lower the volume down a bit from the source to reduce the noise?

Code: Select all | TOGGLE FULL SIZE
void setVolume(uint8_t left, uint8_t right) - Set the output volume for the chip.


No resolution was reached about the changover from the ST --> TI part.

mikeysklar
 
Posts: 5475
Joined: Mon Aug 01, 2016 8:10 pm

Re: Music Maker shield hissing sound

by Corker on Tue Aug 10, 2021 4:36 pm

Lowering the volume has not shown to get rid of the hissing noise.

I discovered, for better or worse, that this problem is intermittent. Both devices exhibited the same behavior, regardless of volume level. But after leaving one of the units alone for a few days and turning it back on the hissing was no longer present. With the hope that this meant it self-resolved I went back to using it only to have it start making the same hissing noise as before after a few hours of use.

Corker
 
Posts: 4
Joined: Thu Apr 20, 2017 11:31 pm

Re: Music Maker shield hissing sound

by Corker on Fri Aug 27, 2021 1:05 pm

I turned the board back on today to see if the problem persisted. What I found was that the shield did not make any noise but was still drawing close to an amp of current. When I touched the amplifier IC it was very hot to the touch. After removing the amplifier IC I was able to use the board as usual with the headphone jack.

Corker
 
Posts: 4
Joined: Thu Apr 20, 2017 11:31 pm

Re: Music Maker shield hissing sound

by mikeysklar on Fri Aug 27, 2021 1:44 pm

@Corker,

You have two Featherwing Shields. Originally both of them had the noise issue. Did they both also exhibit the overheating? It sounds as though you had modified one of them by removing the amp IC. Is that correct?

mikeysklar
 
Posts: 5475
Joined: Mon Aug 01, 2016 8:10 pm

Re: Music Maker shield hissing sound

by Corker on Fri Aug 27, 2021 2:20 pm

I have two Music Maker shields. Both of them have had problems making a hissing sound regardless of whether they were playing an audio file. One of the two boards I turned on today to attempt more troubleshooting but found that the board was consuming an abnormally high amount of power, which also prevented the rest of the system from starting up properly. The amp IC turned out to be quite hot. I removed the amp IC and the power consumption decreased substantially. After the amp IC was removed the rest of the system was able to start up appropriately. Since I no longer had the amp IC I had to use headphones to determine whether the rest of the board was still operational. It is; with the amp IC removed the power consumption is at a normal level and the MP3 decoder IC can play audio files and output the audio to the headphone jack. I have not yet attempted to turn on the other Music Maker shield to see if I experience the same amp IC overheating.

Corker
 
Posts: 4
Joined: Thu Apr 20, 2017 11:31 pm

Re: Music Maker shield hissing sound

by mikeysklar on Sat Aug 28, 2021 11:53 am

@Corker,

Thank you for the clear summary.

I looked at the schematic for the amplifier on the MusicMaker Shield you are using. It does offer a suggestion in terms of speaker resistance in regards to noise and thermal performance. Have you already tried using a speaker with resistance more than 4 ohm?

8388DA23-94E2-482C-9FCB-1831A9F3FBCE.jpeg
8388DA23-94E2-482C-9FCB-1831A9F3FBCE.jpeg (451.82 KiB) Viewed 12 times

mikeysklar
 
Posts: 5475
Joined: Mon Aug 01, 2016 8:10 pm

Please be positive and constructive with your questions and comments.