Problem: No sound coming out of the speakers. In the beginning the sound would come and go. Then the sound stopping became more frequent until being completely mute.
What is working: The headphone output is working fine. With it I could test that the auxiliary input (front panel) is working fine too. Left and right RCA inputs are working. Left and right left and right  6.35 mm (​1â„4 inch) inputs are working.
From the outside the only problem seems to be the speaker.
The cause: After some research I found that this is a common issue for Mackie CR3 Studio Monitors. The root cause seems to be the amplifier chip TDA7265. This chip works fine initially but after some months or years it starts malfunctioning sending a mute signal (output 5) to the board which mutes the speakers. This mute signal should only be triggered when a headphone jack is inserted however in the malfunction the signal is sent continuously.
Solution: cut the ping 5 with small cutting pliers. This stopped the mute signal but also removed the feature of muting the speakers when headphones are plugged. As this worked for me I could replace the TDA7265 chip (around $5) but I will not do that now.
Alternatives: here are some alternative solutions that did not work for me but I read that worked for some.
- Blowing air into the inputs to remove dust and debris.
- Quickly removing and inserting and inserting the auxiliary jack.
- Quickly removing and inserting and inserting the headphones jack.
Conclusion: Don’t buy these speakers. I got it in a bundle deal with some audio gear I bought about three years ago. Speakers should not fail in only three years. The design of this thing is flawed. It heats too much and components start to fail. The amplifier chip seems to be a common issue but when researching this I found switches, I also saw switches, diodes, capacitors, and resistances failing. Even after I fixed it I was hearing some cracking noise in some frequencies.
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