Kef psw2500 green light on but no sound Problems

Question edited for clarity and all the typos.

The Yamaha receiver has to have a sound source and the speaker wires connect the two together. Receivers often have a a switch for Speaker set 1 and Speaker set 2, so you can send the music to two different rooms. Make sure you are on the correct set.

These are supposed to be standalone television speakers by the looks of it connected to what they call an 'AV Processing Unit', I would guess more commonly called a Surround Sound Theatre System. Expensive speakers at $900.

https://assets.kef.com/uploads/files/en/series_pdf/T301_T301c.pdf

https://www.google.com/search?q=kef+t301+no+sound+from+speakers

https://www.google.com/search?q=kef+t301

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It is a 13 year old unit. Take it to a Service Engineer.

https://www.cnet.com/products/kef-instant-theatre-kit540-home-theater-system-5-1-channel/

https://www.audioholics.com/trade-shows/2007-cedia-expo/kef-kit540-kit570

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Based on the information provided, it seems that there may be an issue with the DVD unit of your Kef kit 120. Here are a few troubleshooting steps you can try: Check the power source: Make sure that the Kef kit 120 is properly plugged into a working power outlet. If it is, try plugging another device into the same outlet to ensure that the outlet is working properly. Check the cables: Make sure that all cables are properly connected to the Kef kit 120 and that there are no loose connections. Also, check the cables for any damage or signs of wear and tear. Reset the Kef kit 120: Try resetting the Kef kit 120 by unplugging it from the power source for a few minutes and then plugging it back in. This can sometimes help to resolve issues with electronic devices. Contact Kef customer support: If none of the above steps resolve the issue, it may be a more serious problem with the DVD unit itself. In this case, you may need to contact Kef customer support for further assistance or to arrange for a repair or replacement.

Could be caused by some cabling problem, earth cables touching, or a bad connection.

Either you need new high quality cables,or your amp has output filter capacitor problems.

a capacitor could be overheating and cutting out.then,when it cools you get sound again.this will go on and on until you take it to a tech to get fixed

I wrote to Kef support about an identical issue. Their replay is below.
By the description you have given, it sounds like the power amplifier
board in the subwoofer has failed.

Unfortunately your subwoofer is no longer covered under warranty as the
electronics inside comes with a one year warranty as with all KEF
electronics, and the warranty card would have been supplied inside the
box.

However, you can return the amplifier section to us by removing the
screws on the very outer edge of the back of the unit and disconnecting
the cables inside. Once removed, carefully package the amplifier and
then contact the Service department on 01622 672261 with the serial
number to hand, they will then give you a returns number. Once you have
a returns number, you can send it to the following address with a
covering letter. When sending the parcel, please make sure that you send
it recorded delivery or get a tracking number if sending by courier.

PLEASE NOTE THAT ITEMS NOT BOOKED IN WITH THE SERVICE DEPARTMENT BEFORE
DESPATCH, MAY INCUR FURTHER DELAY.

The address is as follows:

F.A.O. SERVICE
GP Acoustics
Eccleston Road
Tovil
Maidstone
Kent
ME15 6QP

HI,go into the yam setup menu and make sure you have the sub turned on and cross over set to about 80hrtz if this suits your speakers,set sub level to about -5 on amp and say half way on the sub,this should work if not pull out sub cable at amp and touch the end,you should get a hum,if not you may have no power,faulty cable or sub.
PS>make sure you are pluged into the sub PRE OUT and NOT the six channel in.
Hope this helps.
CABLE GUY.

check for the connection og the main wire is cut.. or check the supply..

I have a spare KIT 100 subwoofer unit. contact [email protected] (SW London)