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Asked — Edited
Resolved Resolved by Jeremie!

Soundboardez-B Background Hiss

Hi everyone.

I have a small issue using the EZ-B soundboard and just wondered if anyone experienced this and possibly has a fix. When I play sound files there is a rather annoying hiss in the background.

When I play the sound files directly through a media player on my PC, perfect.

When I use SayEZB() or Pandorabot control, perfect.

But any sound file played through the EZ-B soundboard the background hiss returns. Not a major problem but I would like to eliminate this if I could. Is it possible?



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I seem to be getting the hiss from anywhere between 15 to 100. I haven't gone over 100 as the sounds are loud enough.


With the breakout mod, I found much of the his was gone. I experienced hissing a bit when I had a loud song or noise playing.

United Kingdom

Check the MP3. The built in speaker and amp isn't going to be as good as the speakers & amp on your PC, the hiss is likely to be a part of the track.

Try using Audacity (it's free) to remove hiss and see if it gives better results.

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Sorry, I sould have mentioned that I broke out the EZ-B sound to play through an external amplified speaker.

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Funnily enough the sound files I created where done using Audacity so it's not the MP3 quality, and any other audio such as SayEZB() ect are crystal clear.

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I just got home and I tried reducing the soundboard volume down to 1, and the hiss can still be heard. In fact the volume of the hiss doesn't change when I adjust the volume slider. confused


Hi @Steve G

With the first stage audio breakout the music should be very clean. The reason your are likely seeing the voices come out clean is likely because voice is in a limited frequency range where as music is in a broader range.

A couple things to check:

Is the gain set pretty high on your external amplifier or is it just volume adjust?

Is your audio cable shielded?

Have you tried reflowing your solder joints with a bit of flux?

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Thanks for responding. I don't have a separate amplifier as the speaker has one built in, so no gain control, just a volume wheel which is set to medium level. The audio cable is shielded. It came from an old pair or headphones. And the solder I used had a flux core mix so there shouldn't be a problem there.


Steve G, how is your amp powered ? You may need an additional ground or even a ground loop isolator.

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It is powered by a small rechargable battery housed inside the speaker itself. Below is a picture of the speaker I'm using.

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Aw yes, the issue very well may be that the speaker and ez-b don't share the same ground reference since they have separate power supplies. If you can find a way (maybe through the charging port) to connect the grounds together the noise is likely to go away.

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Thanks for that. Coming to think of it that does make sense. I will give the grounding a try.

Thanks again. :)


My plan with the breakout mod is to get an amplified speaker like you have but power it from the bots main battery. Interested to see if you fix it!

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No worries Technopro. I'll post an update when I try it.

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I experienced a similar annoying hiss when I playing my audio file using the built-in media player. I think that is because there is something wrong with the player. So I download a third-party player to play it. But the same hiss still occurs. I describe this issue to my friend. He suggests that I use an audio editor to remove the noise since the hiss might be from the audio file itself. I employ his recommended Joyoshare Media Cutter. He said that's a reliable audio and video editor that he has been using. Then I try. Luckily, it helps me to eliminate the annoying hiss and won't damage my audio file quality. If anyone who is faced with the same case like me, hope this can be helpful.