Hi,
Not sure if this is the correct section for this topic but please advise if not. I am relatively new to the radio repair side of things and only have limited test equipment at the moment, willing to learn but need advice from the experts.
I have 2 Roberts radio play10 models which are working fine but if I turn the volume past 10 (50%) then the speaker (or heaphones) just stops. Everything on the board looks fine and I've even swapped the audio chip on one of them but the issue is still there. Would it be something as simple as a capacitor somewhere on The board or could It be the headphone jack? Roberts won't release a service manual as its one of the recent models so I'm a little stuck for ideas.

 

Could be a power supply issue, if you have another radio to check with , run the supplies across to each other seeing that you have already changed the audio amplifier, what is the audio amplifier number. ?
( it should be in Technical repair section)

 

Hi, thanks for your reply. I’ve attached a picture of the sound chip which are on the board. I do have another working radio which I’ve swapped parts from and found the following.

power boards swapped and ok, I’ve-installed a new one direct from Roberts.

Speakers swapped out and all fine

It just seems to be on the main board, these radios have a DAB piggyback board which can cause certain issues but I’ve put a new DAB board direct from Roberts themselves. I don’t have access to the service manual but if anyone could give me a link to one then I would be appreciative. It’s just a head scratcher for sure. I will upload pictures of the board when I get back from work to see if anyone can spot something I haven’t.

 

We've had this chip before in a sound fault, here's the circuit from the datasheet.. there's a mute input on pin 8, worth checking..

 

Hi,
That is very helpful thank you. So would that mean it would be on the circuit board rather than the chip because I've replaced the chip with a new one. Not sure how I would check a fault from pin 8 except with my DMM in continuity mode and trying to go from there.
I will have a look later and let you know how I get on. It's just perplexed me with volume ok until it gets above 10/20 then nothing. Actually I do get 2 quiet clicks when I first turn on the radio then it's OK until I turn up the volume past 10.
I'll keep you posted