KORG SP 300 low sounding

[Mr.Migoo]

Hi. I have a SP 300 playing low sound in both speakers and headphone outs. It seems to be a well known desease. I checked other topics about SP series. Some changed 10uf 16V SMD capacitors in the EL-KI-A12 board. Some focus on the mute circuit in the amp board. Does anyone have an advice from where to start to make it sounding again? I have to replace the 2 speakers. Any reference? Thanks for replies.
(I'm sorry for my "french" english).

[The Dude]

Yes, those caps are a known issue. I usually just check all of them with an ESR meter and change any that have high ESR. If memory serves, there is one of the 10uf/16V in the mute circuit that will cause the problem you are having and usually just replacing that one will make the keyboard function normally. However, it's still a good idea to ESR test all of them. You can test in circuit and save a lot of work.

[Mr.Migoo]

I changed all 10uf 16V SMD capacitors (11 pieces) in the main down boards, replaced the damaged speakers, and it sounds great back. Thanks for help , @ thanks to Drewline for the service manual.