i was in the same situation after recapping an se30.

No sound from internal speaker

Good sound from headphones

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turned out it was the headphones socket itself. When u plug in headphones there is a switch in the headphones socket,  that turns off the speaker (its basically a small metal bar mounted on springs)

this small bar was stuck in the wrong position so when you remove the headphones jack it was not going back to its home position to turn on the internal speaker again

there was some grease in there (Dont know if it was to help the connection of movement) - but it was dried up. Just cleaned it all out and reassembled and sound was working

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its a delicate job to open the socket and be careful because when you lift the cover you will see the small components im talking about...dont loose them

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