Hot rodding the Audophonics RPI 4 streamer

Hello everyone -

I have the Audiophonics streamer kit that fits in a very nice case with a color LCD display on the front. It’s a very well thought out kit and it works well when cold. I’m using a powered external USB drive and a wired network connection on it.

I have two issues I’m running into: power and heat.

For the power supply, I’ve used both the stock RPI 4 power supply and an Amazon Chinese 25VA linear power supply. With the standard RPI 4 power supply, Volumio will randomly cut out during playback sometimes. But I never get the lightning bolt icon on the screen.

With the Chinese 25VA power supply (with a heavy duty type C cable), the lightning bolt indicator regularly appears on the screen, but doesn’t effect function. Playback works fine.

I was thinking of modding the RPI by clipping the 5V pins that connect the Audiophonics DAC hat to the RPI 4 and using two separate power supplies. The linear PS for the DAC, the OEM for the RPI 4. Only because I have both already. Is clipping this pins necessary to keep the power isolated on the DAC side or is this not going to yield the intended gain?

The other issue I’ve run into is thermal throttling on the RPI 4 with Volumio. The thermometer icon appears on the screen after listening with Volumio for a few hours and the PI becomes unstable. Enabling the DSP plugin sends it into thermal throttling very quickly.

I read in some other threads, a lot of these streamers were based on the RPI 3 which didn’t have the CPU horsepower than the RPI 4 has. The RPI 3 were fine with ambient cooling.

Hence, cooling is an issue. I’m looking to mod the case to add two 50mm whisper fans powered by a third power supply. Any thoughts on this or other things to look for causing thermal issues? I’m using a large aluminum heat sink attached to the CPU.

Please elaborate on what is connected to what.
Did you power the LCD via the rPi or are you using a seperate psu to power the LCD?
the 25VA should be able to deliver enough power, but make your connections like this:
image

Currently everything is powered via the DAC hat. It has a USB C connector on the back for power, the rPI power port is not accessible without some case mods. I believe a right angle type-C adapter would fit and allow power to be run out the back of the device.

The Audiophonics streamer I have is this one:

https://www.audiophonics.fr/en/open-source-streamers/audiophonics-raspdac-mini-lcd-kit-diy-streamer-for-raspberry-pi-4-dac-es9038q2m-p-15148.html

The LCD is powered by the rPI via the Audiophonics DAC hat board. The Audiophonics unit has a custom board that plugs into their DAC hat. This board also plugs into the display and provides IR for the remote. I don’t believe it’s possible to power it separately without some mods.

I assume what causes the rPI lightning bolt icon is the 5v voltage drops below some threshold? The 25VA PSU has a pot to adjust the output, I’ve tried it at both ends of the range 4.98 - 5.13. It doesn’t seem to make a difference. I haven’t had a meter on the rPI to see what the voltage is on the board when the lightning bolt icon appears.

The issue if you have something connected to the rPi’s USB port, and peak to the max current, the voltage is reduced and the rPi won’t recover and keeps nagging with the yellow thunderbolt thingy.

If you have a DMM, you can turn up the output voltage of the PSU to 5.2 V. As I can’t imagine that Audiophonics would make a bad design.
Since the supplied PSU is doing it’s job, it’s possible that the Chinese wonder doesn’t live up to it’s specifications.

It might be that the rPi runs to hot, you can check the temps via the system plugin or use this python script.

import gpiozero as gz
from time import sleep, gmtime, strftime

min = 100.0
max = 0.0
change = 0

while True:
	cmd = gz.CPUTemperature().temperature
	if cmd < min :
		min = cmd
		change = 1
	if cmd > max :
		max = cmd
		change = 1
	if change == 0:
		sleep(0)
	else :
		print (strftime("%H:%M:%S", gmtime()) + " => Min: " + str('{0:.1f}'.format(min)) + "C, Max: " +  str('{0:.1f}'.format(max)) + "C")
		change = 0
	#print (strftime("%H:%M:%S", gmtime()) + " => " + temp + "C, " + str(int))
	sleep(5)

it will write a line to the shell if Min or Max changes:

16:56:41 => Min: 45.8C, Max: 45.8C
16:56:42 => Min: 45.3C, Max: 45.8C
16:56:46 => Min: 44.8C, Max: 45.8C
16:56:57 => Min: 43.8C, Max: 45.8C
16:57:49 => Min: 43.3C, Max: 45.8C
16:58:25 => Min: 42.8C, Max: 45.8C
16:58:59 => Min: 42.4C, Max: 45.8C
16:59:52 => Min: 41.9C, Max: 45.8C
17:00:41 => Min: 41.4C, Max: 45.8C
17:01:37 => Min: 40.9C, Max: 45.8C
17:03:19 => Min: 40.4C, Max: 45.8C

Hi, I have the same Raspdac Mini and can confirm the frequent power and heat issues. Power issues in my case were resolved by using an Allo Nirvana PS (3.15A at 5V) and mounting a cheap (silent) fan with a micro switch on the back of the device, in case the unit gets hot (typically on summer days). It is an amazing little unit, with high quality performance when it works. I’ve had so many issues that I decided to proceed with a RPi3 with Volumio as a USB streamer (no heat or power issues whatsoever) feeding into a Topping E50 DAC for the serious number crunching. Haven’t looked back ever since.

Read some comments on Audiophonics, that this little thing is very sensitive on it’s power. So this is a bad design form Audiophonics… :flushed: