Speakers blip blip sound

[JeffL]

My Edifier desk speakers have started to make a blip sound which I only noticed the last few days. I recently changed the connection from the 3.5mm headphone jack on the side of my iMac M1 24" to one of the Thunderbolt/USB4 ports on the back of the iMac via an adapter bought direct from Apple (photo attached). I've shut down and powered-up again and also tried one of the USB3 ports on the back and the same problem. I've now connected direct to the headphone jack on the side again and no more blips from the speakers. I'd prefer to connect on the back as it looks far neater but no good if blipping. Any ideas what the problem might be?

 

[chscag]

Just a guess here.... but I suspect the voltage output from the USB4/3 port is causing the "blip" sound to the speaker. The headphone jack output is only audio.

Are the speakers powered?

 

[JeffL]

Just a guess here.... but I suspect the voltage output from the USB4/3 port is causing the "blip" sound to the speaker. The headphone jack output is only audio.

Are the speakers powered?

Hi Charlie - Yes the speakers are powered. Edifier e10 Multimedia Speakers. They are connected to the mains electricity supply (wall plug) via a 12V/20W power adapter supplied with the speakers. There is one Active Speaker and one Passive Speaker. I'm disappointed if, as you suspect, the USB ports are the problem because I did some research before buying the Apple adapter and no one flagged up a potential problem. If you are right, I'll have to buy another adapter , 'L' shaped to plug into the headphone jack to reduce the amount of lead showing from the front of the Mac. Thanks for your reply.

 

[JeffL]

I was thinking the 'L' shaped one but now think the one with the 20cm lead will be less intrusive once I've routed it and stuck it to the back of the iMac.