6 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCH996 Aftermarket Headunit static noise help
Reported repair
Replace head unit and amp
Reported resolution
1
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that report a fix
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Reported fix
When I replaced the head unit and amp with 4 OHM units I had some radio whine but as suggested above, dialing down the gain on the amps solved the problem.
Leading evidence: 'Replace head unit and amp' (1 discussions report resolution; 0 report an unsuccessful attempt). Across 1 matching discussions, the most frequently mentioned possible cause is 'more than likely the signal level' (1 discussions; 1 report identifying it and 0 suggest it). The most frequently discussed action is 'Replace head unit and amp' (1 discussions). For that action, 1 discussions report a resolution and 0 report an unsuccessful attempt. The most frequently reported fix is 'Replace head unit and amp', supported by resolution reports in 1 discussions. These are forum reports and suggestions, not a confirmed diagnosis.
Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that report identifying a cause
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Reported cause
The loudness problem is more than likely the signal level to the amp is being overdriven.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that performed work without a confirmed outcome
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed
I’m generally out of my depth on stereo setups but when I installed an aftermarket head unit, I had to remove the factory amp and run two small Alpine amps.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that performed work without a confirmed outcome
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed
PO of my car had installed new speakers (4 OHM) with the factory head unit and amp (2 OHM) and the setup sounded terrible.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that suspect a cause
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suspected cause
The loudness problem is more than likely the signal level to the amp is being overdriven.
These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.
Replace head unit and amp
1
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that report a fix
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Reported fix
When I replaced the head unit and amp with 4 OHM units I had some radio whine but as suggested above, dialing down the gain on the amps solved the problem.
Discussions that performed work without a confirmed outcome
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed
I’m generally out of my depth on stereo setups but when I installed an aftermarket head unit, I had to remove the factory amp and run two small Alpine amps.
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
I’m generally out of my depth on stereo setups but when I installed an aftermarket head unit, I had to remove the factory amp and run two small Alpine amps.
These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.
Replace head unit and amp
1
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that report a fix
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Reported fix
When I replaced the head unit and amp with 4 OHM units I had some radio whine but as suggested above, dialing down the gain on the amps solved the problem.
Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.
6 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.
0 acknowledgements have no verified action link; they do not establish a repair result.
Generation: 20261026T103553Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
Hello everyone,
I have a 2001 996 Carrera 4 Cab (VIN WP0ZZZ99Z1S643654) with an original PCM1, M490/M680 amplifier in the frunk with a CD changer. I have decided to replace the PCM with an aftermarket Sadocom (Aliexpress) unit that is very well-reviewed. I have replaced the unit fairly easily, and did the plug 17 grounding hack for the M680 amplifier in the frunk. However, during the installation, I noticed that even without plugging in the RCA outputs I had a serious static noise coming from the speakers. I plugged the RCA's and currently have sound but the noise is there always. The static is not dependent on the volume or status of the unit (it happens on ignition with the device muted, on or off), so I think the problem is with the amplifier and it receiving too high of a signal, also when listening to music if I get to 1/3 of max volume it is really loud. Could this be the case, and how could I solve this issue, because the seller is not really cooperating with me?
I have attached the photos (I have the speaker outputs in the yellow plug and no plug B), and how the unit looks now (other than the static it works amazing)
Cables on the back of the PCM1
All cables with PCM removed
When I connect the blue wires (noted AMP) together as noted by the seller I start to get the hiss. If it is unplugged - no sound.
Looks amazing with the new AC screen, cubby and new screen
I used to install car stereos while I was in college. Without knowing more, it sounds like the gain on the amp input side is too high. Some amps have gain adjustments built in. If not, may need to attenuate the input signal with resistors.
Audible static can occur for many reasons such as RF interference, poor shielding, lack of filtering, and all-around substandard electronic components. The loudness problem is more than likely the signal level to the amp is being overdriven. A common mistake is sending the SPEAKER LEVEL output to the amplifier when it is designed to receive LINE LEVEL pre-amp signals. OEM Porsche analog radios that have the separate amplifier in the frunk send LINE LEVEL audio via socket C1 (i.e. YELLOW PLUG).
Reexamine the wiring and report back. Are you using a proper wire harness to adapter the aftermarket radio or splicing?
I’m generally out of my depth on stereo setups but when I installed an aftermarket head unit, I had to remove the factory amp and run two small Alpine amps. The factory setup is 2 OHM impedance and most all aftermarket setups are 4 OHM. PO of my car had installed new speakers (4 OHM) with the factory head unit and amp (2 OHM) and the setup sounded terrible. Lots of static and popping.
When I replaced the head unit and amp with 4 OHM units I had some radio whine but as suggested above, dialing down the gain on the amps solved the problem.
Actually, the factory HAES and Nokia amplifiers as well as the BOSE amps are all pretty much standard 4 ohm setups that can handle 2 ohm loads. The Porsche 996 amps are usually 6-channel (6.1 with sub) systems that feed 4 ohm component speakers in the dash and rear. The factory 5 1/4" full range door speakers and rear/footwell subs are 2 ohm impedance and reason for this is to try to squeeze a little more blood out of the turnip (i.e. amp). A 2 ohm speaker is more efficient and capable of producing more sound when factory systems have a low power output. This is usually more important in the bass and sub bass range to improve the overall depth of sound.
Similar problem with my unit. Hear a slight ticking noise when the amp (blue) connector is plugged in. Without it plugged in there is no sound from the speakers and also no ticking. Was a solution ever found? Would prefer not to buy another amp.
Thanks in advance
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