Power problem - restart loop when plugging usb midi in


#1

Hello,
I've had my Axoloti for over a week now and it's been working great. (Already patched my first synth with it, Yamaha CS5).
But today a new problem started without having changed anything:

First, it connects fine. But, when I plug in a usb midi keyboard, Axoloti starts restarting (leds flashing intermittently) and stays looping in this state, and won't connect again until I remove the usb plug.
This happens with two different midi keyboards and cables.
It restarts (once) even when just touching the ground of the usb jack with the cable's ground, or when just plugging in headphones! Sometimes it even randomly disconnects just by itself, without touching.

I'm currently using usb power, tried 3 different cables with same results, both from computer and a usb power adapter. Strange that yesterday it didn't have any of these symptoms. It worked for days without disconnecting.
Voltage is between 4,97-5V.

Sometimes it gives the following errors upon disconnecting:

Control transfer failed: -9
Ping: WaitSync Timeout, disconnecting now
Disconnect request
java.lang.InterruptedException
java.lang.InterruptedException
at java.lang.Object.wait(Native Method)
at java.lang.Object.wait(Object.java:502)
at java.awt.EventQueue.invokeAndWait(EventQueue.java:1315)
at java.awt.EventQueue.invokeAndWait(EventQueue.java:1296)
at javax.swing.SwingUtilities.invokeAndWait(SwingUtilities.java:1348)
at axoloti.USBBulkConnection.DistributeToDisplays(USBBulkConnection.java:1079)
at axoloti.USBBulkConnection.processByte(USBBulkConnection.java:1258)
at axoloti.USBBulkConnection$Receiver.run(USBBulkConnection.java:868)
at java.lang.Thread.run(Thread.java:745)

Sometimes just the shorter version:

Control transfer failed: -9
Ping: WaitSync Timeout, disconnecting now
Disconnect request

I'm using build version 1.0.12-0-g80370d2, firmware E95BAC96, core V1.2, latest runtime.
Same symptoms with or without SDCard and using two computers, one Win7, one Win10.

I'm suspecting a hardware failure.
Please advise.


#2

Well, today, after a utility power blackout (some repairs with overhead lines were done), everything is fine again.
Both controllers work, no disconnects, all stable.
It was probably some odd general problem with the power lines.
At least good to know that in some circumstances Axoloti can behave strangely while computers still work fine.