I had the same problem and can confirm that the solution with the ON/OFF bridge is working!!! Just solder the two points and you're done!

 

I had been following this thread for months and now I've finally registered.

Guys z533 potentiometer is a dual gang 50k switch potentiometer. it is written a503 in a blind spot of original potentiometer.

there is a switch in it's base. when you turn it to the right, first off switch activates and then power runs to the pcb.

what a crazy potentiometer is this man? just nowhere to be found you know..

what we should do is, we will find an on-off switch first then adjust the volume with a potentiometer separately.

we might need to find another box to put the pcb in it from now on cuz we might not be able to

find the original potentiometer and fit those stuff in original vol control box..

I wrote to the logitech and they could care less you know? Plus this device has a noise when it goes to the idle mode

and it is very annoying but there is also a solution for it.

you guys might bypass the switch function with a simple jumper and use only a potentiometer but there is a slight chance that

one might short circuit the pcb cuz potentiometer's bottom is whole metal you know, yet the original one is plastic.

good luck with fitting the new pot to the pcb.

 

I have found this potentiometer and fixed the device.

Turkiye/Istanbul/Karakoy - Coşkun Elektronik +90 0212 293 71 58

50k stereo linear potentiometer just fits perfectly but you'll need to solder it's leg
by cutting other component's leg and attaching to it.

 

I guys, I found this pot "A50K" I ordered in aliexpress 3€ a couple. Seems very similar to the original one despite the legs direction.

 

I guys, I found this pot "A50K" I ordered in aliexpress 3€ a couple. Seems very similar to the original one despite the legs direction.View attachment 263390

Does this have on and off?

 

you may find the solution here

 

Does this have on and off?

 

Here a sum up:

Problem: one of the two speaker (or both) makes a loud rustle when rotate the volume knob (sometimes the speaker not have any sount at all)

Solution:
1- buy a "A50K" potentiometer link
2- disassembly the PCB from the KNOB
3- cut the 6 long pins of the old potentiometer and remove it dissalding the 2 pins on the bottom.
4- weld 2 short wires on the 2 bottom pads and solder it on the 2 pins on the bottom of the "A50K"
5- weld the other 6 pins of "A50K" on the pins of the old potentiometer, don't fortget to solde also the ground wire, if the tin can't attach scrach a little bit the metal sufcace.
6 - file 1mm the little hole on the plastic case that is the site of potentiometer mark
7 - reassemble the knob

it will work like a new one.

 

Hi,
Three months ago, I have broken the potentiometer of Logitech Z533 speakers. I tried to do a bridge between the two central point (look at the image), and It work.
Now, after three months, the speakers are again break.
I tryed to remake the bridge, but the don't want to work anymore, the speakers doesn't switch on.
Have you any idea?
Thank you, and sorry for my bad English, I'm italian.

Thanks for the tip, got mine working also, this is the second unit I have of these speakers, the first one lasted not even 2 week before I had issue with the volume controller also. Second one lasted until now, so several years but the speakers are 100% still, just the controller that is causing...anyhow, I bridged it and its sorted for now *knock on wood. Cheers

 

Here a sum up:

Problem: one of the two speaker (or both) makes a loud rustle when rotate the volume knob (sometimes the speaker not have any sount at all)

Solution:
1- buy a "A50K" potentiometer link
2- disassembly the PCB from the KNOB
3- cut the 6 long pins of the old potentiometer and remove it dissalding the 2 pins on the bottom.
4- weld 2 short wires on the 2 bottom pads and solder it on the 2 pins on the bottom of the "A50K"
5- weld the other 6 pins of "A50K" on the pins of the old potentiometer, don't fortget to solde also the ground wire, if the tin can't attach scrach a little bit the metal sufcace.
6 - file 1mm the little hole on the plastic case that is the site of potentiometer mark
7 - reassemble the knob

it will work like a new one.

Useful if I have any more issues beyond the quick bridge fix, thanks for making the effort upload these, much appreciated.

 

I have just had the same issues with my volume controller suddenly dying on me, the LED on rotary controller only lights up just at the moment prior to switching off and I can hear the speakers thump as that contact is made, the rest of the radial operation of the volume controller produces nothing and the LED extinguishes as soon as its moved .
I am grateful for the valuable inputs from all the contributors on here and I will attempt a repair soldering a bridge over the two points on the PCB as shown .
I was only told yesterday that there are no spares (potentiometers) for these Logitech speaker controllers which have served me daily for the last 5 years on my PC.
This gives me hope that I may have found a solution.
Sods Law I ordered another set of speakers yesterday as I thought these were toast !
I can always use them on my TV for now
Thanks again for the time and effort people spent building this very informative thread.

 

Update : I tried soldering a bridge across the two pins in the PCB but it still didnt work, but having experienced difficulties in getting the solder to initially "take on the pins" I tried a bench test using a piece of insulated wire between the pins and it worked so even though the bridge seemed secure it obviously wasnt quite bonded , a bit of extra heat and solder cured the problem , very pleased indeed , these are great speakers for the money, had them 5 years and in use daily so they have been trialled for a long period on a daily basis.
I have a brand new spare set coming later which I will keep hold of.
Thanks again to everyone who took time to contribute to the thread !

 

Here a sum up:

Problem: one of the two speaker (or both) makes a loud rustle when rotate the volume knob (sometimes the speaker not have any sount at all)

Solution:
1- buy a "A50K" potentiometer link
2- disassembly the PCB from the KNOB
3- cut the 6 long pins of the old potentiometer and remove it dissalding the 2 pins on the bottom.
4- weld 2 short wires on the 2 bottom pads and solder it on the 2 pins on the bottom of the "A50K"
5- weld the other 6 pins of "A50K" on the pins of the old potentiometer, don't fortget to solde also the ground wire, if the tin can't attach scrach a little bit the metal sufcace.
6 - file 1mm the little hole on the plastic case that is the site of potentiometer mark
7 - reassemble the knob

it will work like a new one.

Thank you very much for this summary, it was really helpful!
I just finished the fix following your guide and it works perfectly again!

 

I've shared the info here, I went to karakoy in Istanbul which is a famous place for semiconductors and elecronics etc.

The Coskun Electronic had this pot for 1 or 2 euros. It just worked great, all i had to do was soldering vertical pins and that's that. Yes it has on and off but no one asked for any help.

 

Hello everyone,

Thanks to this forum I managed to initially fix my speakers by soldering a wire between the on/off switch pins. However, after a few months, the speakers stopped working again. This time, however, the LED light correctly stays on as the switch is still shorted, but no sound at all is coming out of the speakers. Even if I "touch" the aux cable, which should produce some static interference, there is no sound at all.

I thought the potentiometer could be the problem, but I didn't have a substitute and it would take weeks to receive one from AliExpress, so I thought of replacing the 50k potentiometer with 4 25k resistors. I removed the potentiometer and I connected one resistor between the ground and signal pins, and one between the signal and the positive pin, and I did the same with both rows of pins. This way it should emulate a potentiometer set halfway through (if I'm not wrong).

Unfortunately, this didn't change anything and the speakers don't work at all. Does anybody know what could be the cause or what I could try to look into to find the problem?
Something that I noticed is that if I measure the resistance across a resistor (after being soldered) it is not 25kOhm but around 12kOhm, like if there is some other resistance in parallel. I don't know if this is normal, maybe someone could check on their device if it is the same for them.

Here is a photo of the controller with the resistors. The small brown wire is the one the shorts the switch.

 

Here a sum up:

Problem: one of the two speaker (or both) makes a loud rustle when rotate the volume knob (sometimes the speaker not have any sount at all)

Solution:
1- buy a "A50K" potentiometer link
2- disassembly the PCB from the KNOB
3- cut the 6 long pins of the old potentiometer and remove it dissalding the 2 pins on the bottom.
4- weld 2 short wires on the 2 bottom pads and solder it on the 2 pins on the bottom of the "A50K"
5- weld the other 6 pins of "A50K" on the pins of the old potentiometer, don't fortget to solde also the ground wire, if the tin can't attach scrach a little bit the metal sufcace.
6 - file 1mm the little hole on the plastic case that is the site of potentiometer mark
7 - reassemble the knob

it will work like a new one.

i bought in ebay.on jun 4 received on 22 jun.from china to ireland.when ali need 60 days.thank you a lot for photos!i did same.and its working now.

 

Update.so potentiometer change not solve problem. i watched video from this post.so i connect all on vires,and disconnected pod. Sound back.so to bring back pod i guess i need to replace IC. where in video says 4556A NJM4556A SOP8 i found similar.but not sure its good for it. X NJM4556A SOP8 JRC link : ebay please help

 

Found it. It's a R125G.
I see several options on Aliexpress an Amazon. I will order one and see how it works.

I will paste the description and info from this potentiomenter:

Top adjustment type and knurled shaft for easy operate in daily use time.
Main used to control electrical devices such as volume controls on audio equipment.
Knurled shaft with split design for push-on knob.
With turning on/off Switch Function
Model : R125G
Resistance Value : 50K ohm
Adjustment Type : Top Adjustment
Type : Dual Linear(Type B)
Pin Terminal : 8
Shaft Diameter : 6mm / 0.23"
Shaft Length : 13mm / 0.5"
Thread Dia : 7mm / 0.27"
Base Height : 13mm / 0.5"
Material : Metal w Electronic Parts
Package : 1 x Potentiometer（Gasket not included）
Note:Light shooting and different displays may cause the color of the item in the picture a little different from the real thing.The measurement allowed error is +/-1-3 cm.

 

View attachment 287457

I've shared the info here, I went to karakoy in Istanbul which is a famous place for semiconductors and elecronics etc.

The Coskun Electronic had this pot for 1 or 2 euros. It just worked great, all i had to do was soldering vertical pins and that's that. Yes it has on and off but no one asked for any help.

Hi Numano I've been searching this pot for such a long time and I have almost gave up until saw your comment cuz I'm from Türkiye too I'm glad if there is a place that has this potentiometer. BUT when I dial the phone that you provided up there -which has an extra zero but no problem for a local - it was out of use. Do you have any idea what happened to Coşkun Elektronik. Is it still there? Or have any idea where to find the potentiometer ? I'm from sakarya btw which means even if I go there and grab the pot and go back that would cost me more than double the money to order it from China all included.

 

Hi Numano I've been searching this pot for such a long time and I have almost gave up until saw your comment cuz I'm from Türkiye too I'm glad if there is a place that has this potentiometer. BUT when I dial the phone that you provided up there -which has an extra zero but no problem for a local - it was out of use. Do you have any idea what happened to Coşkun Elektronik. Is it still there? Or have any idea where to find the potentiometer ? I'm from sakarya btw which means even if I go there and grab the pot and go back that would cost me more than double the money to order it from China all included.

I've got 1 more. During the day i will try to reach them, if it doesn't work i will get back at you. I'll probably call other shops in there and try to learn whats going on.

Let me figure out stuff first, if things dont work i will post you the potentiometer.