Hi
Power supply is exactly this one https://allo.com/sparky/5v-power-supply.html#features
5V - 3A. (from Xing Yuan XY24S-0503000Q-U)
PSU → Allo Kali Reclocker Barrel 5V input → Power is passed to 1) Allo Piano DAC 2.1 through GPIO & 2) Raspberry Pi 3 through GPIO → A) SSD through USB-2 & B) Wifi Dongle through USB
Power from Kali is shared through GPIO to Allo Piano Dac 2.1 on TOP & Raspberry Pi 3 on BOTTOM through GPIO.
Then Raspberry Pi 3 give power to SSD & Wifi Dongle through USB-2
Hey @laluciol6990,
Thanks for the clarification - this setup sheds light on the actual configuration, but also highlights a critical discrepancy:
The original post said:
“I own a Raspberry 5…”
But this reply describes a power chain that only applies to Raspberry Pi 3:
This is important because Pi 3 and Pi 5 have completely different power and USB architectures. Debugging undervoltage and USB enumeration requires knowing exactly which SBC we’re dealing with.
Please use the following link to generate an SBC identification form:
Or run this directly via SSH:
cat /proc/device-tree/model
Expected output for Pi 3:
Raspberry Pi 3 Model B Rev 1.2
Expected output for Pi 5:
Raspberry Pi 5 Model B Rev 1.0
Once we have positive identification, we can proceed with the correct diagnostics. Power routing and USB stack behavior vary significantly between Pi 3 and Pi 5 - especially with chained devices like the Kali and Piano DAC.
Let’s confirm this before digging deeper.
Kind Regards,
Sorry for the confusion
The original poster mentioned a Raspberry model.
I joined the thread because of the M.2 SSD mounting issue, but my Raspberry Model is, according to the command you suggested: “Raspberry Pi 3 Model B Rev 1.2”
Hey @laluciol6990,
Thanks for the details. Full power path breakdown - this matches what we’d expect for an Allo stack powered via the Kali reclocker. The PSU used (Xing Yuan XY24S-0503000Q-U, 5V 3A) is within spec on paper, but the actual layout introduces multiple weak points under load:
[5V 3A PSU]
↓
[Kali Reclocker 5V Barrel Input]
↓ GPIO
[→ Piano DAC 2.1 (top)]
[→ RPi 3 (bottom)]
↓ USB
[SSD] + [Wi-Fi dongle]
This creates a single-rail, passive distribution tree with no power buffering or current prioritization. Issues:
The kernel’s undervoltage warning (hwmon hwmon1) is a direct result of this design - even if average load is acceptable, brief voltage dips are enough to trigger this error.
Use a powered USB hub for Wi-Fi and/or SSD
Inject 5V directly to the Pi’s USB rail
Switch to a beefier PSU with tighter voltage regulation
Add local capacitance
Run this command via SSH:
vcgencmd get_throttled
Sample output:
throttled=0x50000
Then interpret the bits:
| Bit | Meaning | Value |
|---|---|---|
| 0 | Under-voltage now | 0x1 |
| 1 | Frequency capping now | 0x2 |
| 2 | Throttling now | 0x4 |
| 16 | Under-voltage has occurred | 0x10000 |
| 17 | Frequency capping has occurred | 0x20000 |
| 18 | Throttling has occurred | 0x40000 |
If you see:
throttled=0x50000
It means:
To monitor over time and log when undervoltage occurs, use this shell script:
#!/bin/bash
LOGFILE=/home/volumio/undervoltage.log
INTERVAL=60
while true; do
STATUS=$(vcgencmd get_throttled)
TIMESTAMP=$(date '+%Y-%m-%d %H:%M:%S')
echo "$TIMESTAMP $STATUS" >> "$LOGFILE"
sleep "$INTERVAL"
done
Save as monitor_uv.sh, then run:
chmod +x monitor_uv.sh
nohup ./monitor_uv.sh &
This will log entries like:
2025-04-14 21:30:01 throttled=0x0
2025-04-14 21:31:01 throttled=0x50000
You can later grep for events:
grep -v 'throttled=0x0' undervoltage.log
Kind Regards,
Thanks for so much details!
I would check to put the script in place this weekend when i have some time.
Regarding the possible solutions, i think the easiest is to buy a beefier & better regulated PSU, like 5V >4A, industrial or medical grade from Mouser/Digikey or electronic components website…
Others solutions are a bit more complex or i don’t have the necessary knowledge…
But thanks again for the pointers!
Powering the device, no music playing or anything
“throttled=0x50005”
I had to add some command because i was told
“2025-04-26 08:43:52 Can’t open device file: /dev/vcio
Try creating a device file with: sudo mknod /dev/vcio c 100 0”
I did it on the terminal
But then, for the script, i am a bit at a loss to make it working while trying to integrate the mknod…(i am not a programmer / used to bash scripting)
Hi
Some updates, if situation could be further improved…
Not expecting specifically an answer, but if somebody know how to improve further…
(will look into the capacitance thing)
More updates on 05/04/2025
To avoid throttling, one way was:
a. remove a jumper on Kali board to separate power between Kali & Raspberry Pi
b. connect 5V 6A PSU to Raspberry Pi through Micro-USB
c. connect 5V 3A PSA to Kali board
This is a 2 PSUs solution, a bit cumbersome so i will see if i can create a specific cable to have the 5V 6A PSU power Raspberry Pi through Micro-USB & Kali through barrel connector
One question to @nerd : Could i try to solder the capacitor on the GPIO direclty where the power from Kali would come from originally (5V & GND)?
Just for reference: this page https://blog.mccormack.tech/shell/2019/01/05/monitoring-raspberry-pi-power-and-thermal-issues.html helped me greatly interpreting the vcgcmd command results
Have a nice day
Last set of updates: 16/05/2025
PSU 5V 6A with a split cable: 1 wire going to Allo Kali (without the jumper, so Kali doesn’t power the Raspberry Pi anymore), 1 wire going to the Raspberry Pi (powered through micro-usb port)
I get “throttled=0x50000” with the SSD connected
I will let it at that
