jspinski
USA
Asked
— Edited
I am having an issue with my V4 audio volume, I had the audio working fine, and I had used a breakout I saw from Dave S, since I am doing the same sort of project as him, it went from the Via out to an external amp which worked fine, then when I connected the external speaker to the amp it worked amazingly. Then I shutdown for the day by turning off the amp first and came back today and went to start up my EZb and all of the audio coming out of it is almost un-hearable. I tried all the mentioned here https://synthiam.com/Community/Questions/8755 and nothing seemed to work.
If you can hear the audio a little, then i would test your amp
If the amp is indeed working, then check the wiring
I have tested my external amp using both my phone and my laptop, the amp works fine, when I connect my EZ b the audio is very quiet. Not only that when I try to use the on board speaker and amp that is in the ez b I can only hear it if I put it right next to my ear, since it is so quiet. I've made sure that the springs on the speaker are connected properly and still no difference
Where did you connect the external amp to the ezb? Did you connect the amp to the speaker terminals?
I connected the audio here and to the ground on the upper right, the one in the center labeled GND
Check the solder connection to see if the heat melted through the surrounding protective layer and is causing a short to ground. A continuity test with a electronic meter will help.
I do not think that it is an issue with the external connection, that system works fine when connected to something else. I did a continuity check on the connections I made and everything seems to be alright there. Even without my external setup the ez b itself seems to have no volume to it, like its getting a bad connection to the speaker but from what I can tell it is making a good connection. I work for an electrical engineer so I know what is going on for the most part, whatever the issue is it seems to be something with the v4 unit itself, what that is I do not know. When I hit the reset button on the V4 I can barely hear the voice telling me what is happening. As of the first post I made I had completely disconnected my leads and reverted it back to as I had never modified it in the first place.
Please check the solder connection on the ezb to ensure it has not melted the nearby ground shield and shorted. You can use a multimeter for the test.
The audio pin that you've connected to is direct to the DAC I/o of the stm32 arm CPU. If it was accidentally shorted, it may be damaged. However, since there's a little bit of audio coming through, I'm guessing the dac may be fine but it is shorted to ground at the pin on the ezb.
As @DJ mentioned, it could be that there's a short somewhere. Please test the audio input pad to Ground, if the audio input pin is isolated it should read in the 3 MegaOhm range. I suspect that the EZ-Bv4 processor or the audio amplifier chip has somehow been damaged, through static build up or otherwise, and is pulling down the audio. Unless the volume in the EZ-B soundboard control is just turned all the way down.