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Hi,
My keyboard turns on but no sound from speaker or headphones. Have done a.factory reset. Sound xame back very quietly for about 2/3min then went. That was only a few times, now nothing.
Opened it up, everything looks totally fine. No loose wires, circuit board look fine.
Any ideas.
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Hi @janebryan
You may have to start checking the sound circuit to find out what's wrong.
Can't find a service manual for a P-45 but here's one for a P-45B which may help. Hopefully there's not too much of a difference.
Looking at the block diagram on p.100 (of 109), the headphones and the speakers use different circuits i.e. the headphones use a DAC (digital analogue converter) and the speakers use a digital amplifier and the only common point for the sound, is their inputs (or output from the CPU if you prefer). Put simply when a piano key (or keys) is pressed a signal is sent to the CPU which knows what tone to send to either the speakers or the headphones
Perhaps start by checking if the cable between the PN board and the DM board is securely connected at both ends. Also that the power rails have the correct voltages e.g. +12V, +3.3V etc.
If the above checks seem OK I think that it will need circuit testing with a DMM (digital multimeter) at board level to find out what's wrong
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Hi @janebryan
Does moving the volume slider back and forth cause any sounds (even a crackling/static sound) to be heard at all?
crwdns2934271:0crwdnd2934271:0 jayeff crwdne2934271:0
Hi, No crackling sound.
crwdns2934271:0crwdnd2934271:0 Jane Bryan crwdne2934271:0
That's really helpful, thanks so much. Will have a look into this and let you know. Thanks again.
crwdns2934271:0crwdnd2934271:0 Jane Bryan crwdne2934271:0