Topping D90LE sound output suddenly stops after few hours of listening

[d0j1n]

I experienced something strange 2 days in a row. After listening with my Topping D90LE/A90 stack (connected via xlr) for 2-3 hours (source: iPhone through USB) my headphones stop playing any music. The DAC still displays an incoming signal (showing that it receives 48 kHz signal). I disconnected, reconnected, restarted apple music on my iPhone, also connected the DAC to my iPad, turned the DAC off and on in the front. After each step trying to fix the problem the iPhone / iPad seemed to stream music to the DAC and the DAC shows the kHz of the signal it receives but still there is no sound output to my headphones. The only way I get back the sound is by turning the DAC off and on using the power switch on the back. Did anyone else experience a similar behaviour? Any ideas how to to fix this? Seems to be a firmware bug rather than hardware. But that is just my guess.

 

[restorer-john]

Seems to be a firmware bug rather than hardware.

That's not a bug, it's a unique Topping feature!

A bit like Apple's health app that tells you to turn down your music, except Topping decides you've listened long enough and mutes your headphones.

 

[Dunring]

I'd check your phone and player settings for power management. In some of my android players there is and in Android you can set if an app has no restrictions on battery use, or if it's optimizing it, or none at all. Not familiar with Apple but I'm certain they have something similar. I've had the D90se a few times and never had an issue like that. I'd also check the firmware and flash the latest on the DAC. Last times I did they added some cool filters and modes to play with. The tube one really didn't sound like a tube amp, but it was ok. Might be worth it just for a bug fix possibility.

 

[d0j1n]

I'd check your phone and player settings for power management. In some of my android players there is and in Android you can set if an app has no restrictions on battery use, or if it's optimizing it, or none at all. Not familiar with Apple but I'm certain they have something similar. I've had the D90se a few times and never had an issue like that. I'd also check the firmware and flash the latest on the DAC. Last times I did they added some cool filters and modes to play with. The tube one really didn't sound like a tube amp, but it was ok. Might be worth it just for a bug fix possibility.

Thanks for your suggestions. Since I reconnected the devices and restarted the apps and also toggled the front power switch on the D90 I dont think energy saving is the issue. Also I can't find any new firmware for the d90le offered on toppings website, only d90se is listed.

 

[d0j1n]

Update: Connected the DAC directly to active speakers instead of going though A90. Also switched power cable and usb cable. Error didn't occur over a duration of 3.5 hours. Have to continue testing.

 

[MAB]

Update: Connected the DAC directly to active speakers instead of going though A90. Also switched power cable and usb cable. Error didn't occur over a duration of 3.5 hours. Have to continue testing.

Have you tried RCA hookup to the A90? I ask because I wonder if the DAC is fine and the output may be the issue. Also, the balanced input impedance to the A90 is 2kOhm, RCA is 10kOhm, don't know if this low impedance specifically on the balanced input is causing a marginality in the D90's output. You could hook up RCA and XLR, let it cook for a few hours until it drops out and see if it also lost the RCA signal.

Hard to arm-chair diagnose. Frustrating since it takes a few hours to happen. I can imagine lots of things, like bad solder/assembly manufacturing combined with thermal load over time. Have you contacted Topping or the reseller? How long have you had the unit?

 

[d0j1n]

Have you tried RCA hookup to the A90? I ask because I wonder if the DAC is fine and the output may be the issue. Also, the balanced input impedance to the A90 is 2kOhm, RCA is 10kOhm, don't know if this low impedance specifically on the balanced input is causing a marginality in the D90's output. You could hook up RCA and XLR, let it cook for a few hours until it drops out and see if it also lost the RCA signal.

Hard to arm-chair diagnose. Frustrating since it takes a few hours to happen. I can imagine lots of things, like bad solder/assembly manufacturing combined with thermal load over time. Have you contacted Topping or the reseller? How long have you had the unit?

Thanks for your feedback! Will try that. Good idea! I contacted topping. They suggested to test without a90 and also to switch the usb cable. Problem is that I changed everything at the same time so now I don't know what healed it. First I will try to reproduce the error once more and then I will change one part at a time and also try your suggestion. Have the d90le for 2 months now but just started using it a lot recently.