Hello everyone,

I've been using a pair of Mackie CR5XBT speakers for about two years. Recently, I've encountered an issue where there's no sound output from the speakers themselves. However, when I plug in headphones to the front jack, I can hear audio.

As a troubleshooting step, I tried cutting the 5th pin on the TDA7265 chip, which temporarily restored sound. Unfortunately, this introduced a persistent buzzing noise.

To address this, I purchased a new TDA7265 chip and replaced the old one. However, the problem persists: no speaker sound and headphone sound only.

I don't have any electronic expertise or testing equipment. I've read a suggestion to cut the 5th pin and bridge it to the 9th pin, but I'm unsure how to proceed.

Any advice or guidance would be greatly appreciated.

 

The 5th pin on the TDA7265 chip is the mute/standby control. If this pin is grounded or has the wrong voltage, it can mute the speakers.

 

The 5th pin on the TDA7265 chip is the mute/standby control. If this pin is grounded or has the wrong voltage, it can mute the speakers.

so the cause of wrong voltage could be the mulfunction of another component ? like a dead diode? z3 & z4? witch i should buy to replace?
(Zener 12v 1w 1n4742a)
(Zener 12v 5w (1n5349b))

 

so the cause of wrong voltage could be the mulfunction of another component ? like a dead diode? z3 & z4? witch i should buy to replace?
(Zener 12v 1w 1n4742a)
(Zener 12v 5w (1n5349b))

Check for visible damages like cracks, discolouration, or overheating signs. Also, check with a multimeter.