Topping L30 ii Interference Issue

[Taschenrechner]

I changed RCA cables, I switched AC sockets, I checked without RCA cables, tried a different DAC. I tried grounding the unit. Nothing really helps. How can I fix this? It worked fine the first few weeks.

 

[Human Bass]

The rca cables seem to be the source of the problem, since it gets stronger when you place the cellphone in the back near them.

The most well shielded rca cables I know are World Best Cables with the Gotham Ultra Pro Gac-1. Coaxial with 4 layers of shielding.
2 Foot RCA Cable Pair - Gotham GAC-1 Ultra Pro - Low-Cap (21pF/ft) Audio Interconnect Cable with Amphenol ACPR Die-Cast, Gold Plated RCA Connectors https://a.co/d/0NnVSnU

Avoid any rca cable that isnt coaxial. 2 and especially 4 conductors rca are awful at avoiding interference. Also the whole "directional" shielding is bullshit in my experience.

In the case the problem persists, a balanced system is the only solution.

 

[Taschenrechner]

The rca cables seem to be the source of the problem, since it gets stronger when you place the cellphone in the back near them.

The most well shielded rca cables I know are World Best Cables with the Gotham Ultra Pro Gac-1. Coaxial with 4 layers of shielding.
2 Foot RCA Cable Pair - Gotham GAC-1 Ultra Pro - Low-Cap (21pF/ft) Audio Interconnect Cable with Amphenol ACPR Die-Cast, Gold Plated RCA Connectors https://a.co/d/0NnVSnU

Avoid any rca cable that isnt coaxial. 2 and especially 4 conductors rca are awful at avoiding interference. Also the whole "directional" shielding is bullshit in my experience.

In the case the problem persists, a balanced system is the only solution.

I did also try the same test without any cables connected and different RCA cables. But the problem persists. I do not believe it's the RCA cables. Seems to be some grounding issue. The unit does have some grounding screws. I tried grounding it with those but it only lowers the volume of the interference a tiny bit.

 

[Human Bass]

Also do those 2 simple (separated) tests:

Disconnect the rca cables of the L30 and check if there is still noise or not.

Put your cellphone on airplane mode and see if the interference still happens.

 

[Human Bass]

Did you try a direct wire from the chassi to the ground outlet of your house? I had a similar problem with my A50S picking up a radio station, but it was mainly due to the rca cables.

I did also try the same test without any cables connected and different RCA cables. But the problem persists. I do not believe it's the RCA cables. Seems to be some grounding issue. The unit does have some grounding screws. I tried grounding it with those but it only lowers the volume of the interference a tiny bit.

 

[Taschenrechner]

Also do those 2 simple (separated) tests:

Disconnect the rca cables of the L30 and check if there is still noise or not.

Put your cellphone on airplane mode and see if the interference still happens.

First test I already did and no change in the issue.

Airplaine mode of course solves the issue as no RF is getting picked up. But there might be accational interference from it.

 

[Taschenrechner]

Did you try a direct wire from the chassi to the ground outlet of your house? I had a similar problem with my A50S picking up a radio station, but it was mainly due to the rca cables.

yeah thanks for the help so far. And I don't want to f arround with the ground rod of my flat.

 

[Human Bass]

First test I already did and no change in the issue.

Airplaine mode of course solves the issue as no RF is getting picked up. But there might be accational interference from it.

This noise is very common, i remember when i was a teen and we knew a calling was coming because our speakers would do this very same noise a few seconds before.

 

[Taschenrechner]

I tested it again with a replacement unit. Same issue. I used new co-axial cables.

 

[Taschenrechner]

Solved the issue with laying a 2mm thick steal plate I had laying around on top of my desk. Now the L30 ii stopped picking up my phone signals.