Mekede M6 Pro 2k + Hertz speakers + JBL 5ch = hum/whine ??? Help please

johnnyb_aussie

CarAudio.com Newbie
Installed the m6pro plus 2k, was super happy with it... until i installed hertz speakers all round and jbl 5ch amp.

There is feedback hum/whine through the speakers. This hum/whine was is not present if I connect the speakers to the headunit directly using the headunit built in amp.
(ran this way for 5months)

The hum/wine only occurs when a rca is connected to the headunit, this occurs on the front rca, rear rca and sub out rca, the hum/whine affects all output rca's.

With the rca's disconnected from the headunit there is no hum/whine from the amp/speakers (amp powered on by headunit just no rca's to headunit),

Only once a rca is connected to the headunit does the hum/whine occur, occurs on all speakers and all channels regardless of rca used (front/rear/sub).

if rca to front right only connected to the headunit, thats the only channel that he hum/whine occurs on. If rca to front left is connected to headunit thats the only channel the whine occurs on... so the whine is directly related to the rca being connected to the headunit.

Anyone connected their m6pro to a external amp using the rcas?

i have tried disconnecting all aux leads - reverse camera, wifi, 5g, mic, gps to eliminate those from being the cause.

Anyone a) experience this b) using the m6pro 2k connection to external amps?

My wiring is top notch, high quality 12gauge ofc, 4gauge power+ground, high quality rcas, all wire ends high quality connectors with heatshrink and attention to detail. Built many car audio setups over the years, first time ever had a hum/whine.

Thoughts? thanks guys
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thanks.
 
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Do you have another HU /older HU you pulled out with at least one set of RCAs on it?
These cheaper aftermarket Androids usually have some type of issues due to poor shipping,sitting in an improper storage environment ect usually. Though..there may be a setting issue to change in the menue to turn off onbaord amplifier. I havent installed that particular unit myself. How old is the JBL 5 ch amp?
 
yes, the 8core+256gig 10.1" the top model, the device is amazing, full dsp, 2k screen, the sound from the headunit built in amp is excellent.. the functionality from the DSP has everything, highpass/lowpass/bandpass, dts, its a fantastic headunit..
Id have to read on it a bit. there may be something in settings to turn off internal amplifier to use the RCAs external input.
 
Do you have another HU /older HU you pulled out with at least one set of RCAs on it?
These cheaper aftermarket Androids usually have some type of issues due to poor shipping,sitting in an improper storage environment ect usually. Though..there may be a setting issue to change in the menue to turn off onbaord amplifier. I havent installed that particular unit myself. How old is the JBL 5 ch amp?
hertz pro and jbl all new, as stated in the post the amp and speakers without the rca dont have any feedback. I dont have the oem headunit (no rca anyhow). Tomorrow i am going to connect the headunit to my soundbar and test that, if feedback is present then its the headunit rca. Then ill connect my laptop to the amp via rca and test that.
 
Id have to read on it a bit. there may be something in settings to turn off internal amplifier to use the RCAs external input.
no gone through all the settings too, i worked in IT for 25yrs and am very thorough and methodical. Super annoying after spending days on 20kg of sound deading, all the wiring, mounting all to have this whine... super annoyed.
 
thanks for the input, i am hoping someone here has used this headunit in the top model form and can confirm the rca's are not the cause... or they are or this is faulty somehow.
 
no gone through all the settings too, i worked in IT for 25yrs and am very thorough and methodical. Super annoying after spending days on 20kg of sound deading, all the wiring, mounting all to have this whine... super annoyed.
Have you tried just a single ground wire for the HU yet to test on a solid location or a possible bad ground on floating ground issue
 
no gone through all the settings too, i worked in IT for 25yrs and am very thorough and methodical. Super annoying after spending days on 20kg of sound deading, all the wiring, mounting all to have this whine... super annoyed.
Some of the newer vehicles the HU dont really have a solid ground and float off the Plug and Play wiring harness
 
Have you tried just a single ground wire for the HU yet to test on a solid location or a possible bad ground on floating ground issue
No i have not changed the ground that was made when i installed 5mths ago, been running without whine/feedback/hum on the internal amp so didnt think the ground could be to blame. But i will try regrounding the headunit tomorrow, thanks for that idea/test.
 
No i have not changed the ground that was made when i installed 5mths ago, been running without whine/feedback/hum on the internal amp so didnt think the ground could be to blame. But i will try regrounding the headunit tomorrow, thanks for that idea/test.
I see you have the same type of wire strippers that I use and crimpers. You can just take the strippers and spread the ground wire on the harness without making a cut/ just push/ strip the wire to expose copper without having to cut it keeping the harness in tact and tap a new ground wire there and run it to a testing location. If it doesnt solve it, it doesnt really hurt to have that extra ground wire anyways, or cap it back off. One wire to test with. 14ga or 16ga wire works just fine. worth a shot
 
I see you have the same type of wire strippers that I use and crimpers. You can just take the strippers and spread the ground wire on the harness without making a cut/ just push/ strip the wire to expose copper without having to cut it keeping the harness in tact and tap a new ground wire there and run it to a testing location. If it doesnt solve it, it doesnt really hurt to have that extra ground wire anyways, or cap it back off. One wire to test with. 14ga or 16ga wire works just fine. worth a shot
thanks, will spend sometime tomorrow and reground the headunit and do some testing of other inputs to the amp to isolate the headunit.
 
Might even try to pull the Fuse on the HU to power it down or HU wiring harness, and put RCAs in and wait a little bit put back in to see if it resets back to normal settings even? I had do that with a Blaukpkt. HU before, and a newer Kenwood one in the past. May even look to see if there is a Firmware update out on that HU may solve the issues as well?
 
Might even try to pull the Fuse on the HU to power it down or HU wiring harness, and put RCAs in and wait a little bit put back in to see if it resets back to normal settings even? I had do that with a Blaukpkt. HU before, and a newer Kenwood one in the past. May even look to see if there is a Firmware update out on that HU may solve the issues as well?
thanks will have a look and see if anything i do changes the whine. As the unit boots up the whine changes, before the bootlogo shows the whine is really loud, then it boots fully and the whine changes to a lower volume and lower tone, weird.. super annoying after spending so much cash on all that new gear and the hours of sound deading and foaming and rattle/vibe reduction... once i put music on man does it sound superb.. its the best sound caraudio setup ive built, all that work on sound deading and fastrings and hertz speakers was worth it..
 
thanks will have a look and see if anything i do changes the whine. As the unit boots up the whine changes, before the bootlogo shows the whine is really loud, then it boots fully and the whine changes to a lower volume and lower tone, weird.. super annoying after spending so much cash on all that new gear and the hours of sound deading and foaming and rattle/vibe reduction... once i put music on man does it sound superb.. its the best sound caraudio setup ive built, all that work on sound deading and fastrings and hertz speakers was worth it..
That is strange there. Thats what Ive encountered with low voltage before . That Kenwood needed a Firmware update and that fixed that one when it was BNEW Kenwood Excelon KDC-X996 unit
 
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