Based on one of my previous posts (no sound)

After some research I managed to repair myself the BM54.
Now I have a great sound but there is a whining noise only when the cassette player (I use it to connect to the smart phone to ear music) and the cd changer are connected.
It get worst when the engine is running.
Srangely this not happens when on the radio mode.
I know I'm not a technician and the repairers are laughing whit this, but, can someone explain me why this happens and wht can be the solution?

Cheers

Sounds like (excuse the pun) the problem you used to get in the old days on a car stereo, when you needed to fit a capacitor in the line somewhere to prevent interference from the engine's electrical components.

Possibly something similar inside the BM54 not doing its job? .
Experience is the only genuine knowledge, but as time passes, I have forgotten more than I can remember
Volvo V70 P2 2006 2.4 Petrol 170bhp Estate SE
MG Midget Mk1 1962

Previous: L322 Range Rover TDV8 3.6 2008; L322 Range Rover TD6 3.0 2002; P38A Range Rover V8 1999

This only happens after I removed the old amplifiers and installed the new ones (http://www.ebay.co.uk/itm/2-x-50W-TDA7492-D-Class-High-Power-Digital-Amplifier-Board-AMP-Board-Radiator-/172403320436?hash=item282409e674:g:4m0AAOSwB09YIbK6) that came from China.

As I said I'm not na electronic technician and probably I've done something less correctly.
Anyway we have very good radio stations all over the country here in Portugal.

Cheers

I think you can buy inline suppressors to cut out that whining, revving noise that accompanies the engine revs. I'm showing my age now  ______________________________
Simon
______________________________

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