Loopy Pro: Create music, your way.

What is Loopy Pro? — Loopy Pro is a powerful, flexible, and intuitive live looper, sampler, clip launcher and DAW for iPhone and iPad. At its core, it allows you to record and layer sounds in real-time to create complex musical arrangements. But it doesn’t stop there—Loopy Pro offers advanced tools to customize your workflow, build dynamic performance setups, and create a seamless connection between instruments, effects, and external gear.

Use it for live looping, sequencing, arranging, mixing, and much more. Whether you're a live performer, a producer, or just experimenting with sound, Loopy Pro helps you take control of your creative process.

Download on the App Store

Loopy Pro is your all-in-one musical toolkit. Try it for free today.

Quiet disturbance in audio signal starts when IPad akku has reached 100% charge

DeepsoulDeepsoul
in General App Discussion

Hello,

I'm experiencing a faint, mid- to high-frequency static noise with my setup as soon as the battery reaches 100% charge. The noise is irregular, sometimes a slight crackling, sometimes a bubbling, sometimes a whirring.

When the battery is still drawing a significant amount of power, there's no noise. Everything works perfectly even without the power adapter.

ChatGPT told me that the power adapter reduces its output when the battery is full, which then causes this noise. That makes sense to me.

Before I try other power adapters and hubs, here are my questions:

Has anyone else had this problem and found a solution?

Which power adapter doesn't produce this noise?

Could it be the USB hub?

My setup:
iPad 2025/11" (A16)
Acer USB-C Hub, 7-in-1 USB-C to 4K HDMI, 2x USB 3.0, 1x Type-C 5Gbps, 100W PD
ANKER 313 45W IQ Power Supply
Behringer UMC404HD Audio Interface

This text has been automatically translated; I hope it is understandable :O

Comments

  • SevenSystemsSevenSystems

    Yes, the AI is correct. It's hard to say how to find a power adapter that doesn't have this issue, because it's something you'll never find in consumer-grade specification lists.

    In general though, the higher the price, the more likely it is to use higher frequencies for regulating the power transfer and thus the less likely they are to be audible.

    How about this: connect something else to the power adapter that ALWAYS draws power (like a light or something), avoiding the low-power state that causes the issue?

  • EtienneEtienne

    Also, how do you hear the noise ? Speakers, headphones ?
    One time I had a high pitched noise that drove me insane, but the sound was coming from one power adapter itself, lol.

    Also, is your umc404hd powered by usb or do you use the adapter ?

  • DeepsoulDeepsoul

    @SevenSystems said:
    Yes, the AI is correct. It's hard to say how to find a power adapter that doesn't have this issue, because it's something you'll never find in consumer-grade specification lists.

    In general though, the higher the price, the more likely it is to use higher frequencies for regulating the power transfer and thus the less likely they are to be audible.

    How about this: connect something else to the power adapter that ALWAYS draws power (like a light or something), avoiding the low-power state that causes the issue?

    Yes I tested some LED lights on one usb port, but the amount of power that those need is way too low. Probably I will test a DIY solution made out of an old bicycle bulb plus a resistance parallel on one usb port.

  • SevenSystemsSevenSystems
    edited November 2025

    @Deepsoul said:

    @SevenSystems said:
    Yes, the AI is correct. It's hard to say how to find a power adapter that doesn't have this issue, because it's something you'll never find in consumer-grade specification lists.

    In general though, the higher the price, the more likely it is to use higher frequencies for regulating the power transfer and thus the less likely they are to be audible.

    How about this: connect something else to the power adapter that ALWAYS draws power (like a light or something), avoiding the low-power state that causes the issue?

    Yes I tested some LED lights on one usb port, but the amount of power that those need is way too low. Probably I will test a DIY solution made out of an old bicycle bulb plus a resistance parallel on one usb port.

    Sounds good! BTW, I wasn't sure if the noise is coming from the power supply itself or propagating through your audio chain -- if it's just coming from the unit itself through the air, you might try just wrapping the unit in some kind of fabric -- high audio frequencies are quite easily blocked by even thin fabric.

    (watch the heat though)

  • DeepsoulDeepsoul

    @Etienne said:
    Also, how do you hear the noise ? Speakers, headphones ?
    One time I had a high pitched noise that drove me insane, but the sound was coming from one power adapter itself, lol.

    Also, is your umc404hd powered by usb or do you use the adapter ?

    Yes, the noise is really on the headphone.

    My 204HD interface is plugged in the above mentioned USB Hub which is connected to the IPad and the Anker power device.

  • DeepsoulDeepsoul

    Update:

    Now I had the chance to test a Zoom H6 connected via USB.
    With this device I wasn't able to hear any of that noise :)

    What I noticed with the 204HD: the noise was NOT inside the recordings of Loopy pro.
    It is "somewhere" in the audio signal but perhaps just in the outgoing signal circuit.
    I tested both the headphone and the cinch outputs. On both I can here that noise.
    But nothing in the recordings... strange thing!...

Sign In or Register to comment.