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As a heads up, the LM3915 chip has two modes. The first is a dot mode (where one LED it lit up at a time) and the second is a bar mode (where all the previous LED's are lit up). This is controlled by pin 9. When 9 is pulled to high the chip is in Bar mode, when disconnected it is in dot mode. J3 allows pin 9 to be connected to the V+ rail. It looks like the jumper was not part of the kit/omitted from the instructions. Using bar mode makes the LEDs brighter (they are always on) and, in my case, made one of the lower LED work. I suspect the high sample rate and dot mode combine to effectively control the LED brightness by Pulse With Modulation (PWM). If the low LED's are not being triggered much during a track/song, they get perceived as dead/off. Switching to Bar eliminates the PWM effect on the lower LED's, allowing these "dead" LED to work. Hope this helps, if nothing else it gives another option in your setup.
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