DirectStream USB display color question?


#1

I am having an issue with my USB connection to my new DirectStream DAC. Should the USB display dot color on the DS turn “red” from “green” when the computer connected to it is shut off and should it turn “red” when the USB connector is pulled out of the DS? Sometimes the color on my DS USB display turns “red” then back to “green” shortly after I turn off the computer or pull the USB connector from either my DS or computer? From what I understand this is not normal? Correct?

Thanks,

Bob


#2

Howdy Bob

It is intended to be green when a computer is hooked up. What the DS’s USB can really see from the USB line varies a little depending on your USB hardware, including hubs. For example, unfortunately, it isn’t doing an active handshake with a USB driver that could indicate whether an app wanted to talk to the DS.

It is the case that it goes from red to green and back a couple of times as my computer boots or closes down. But being green when the computer is off isn’t something I’d expect.

With an older version of the XMOS code (one not released to anyone out side of PS Audio) I would have the problem that the USB wouldn’t work at all if the DS was on when the computer booted.

On the off chance that your problems are related to something like this, power the DS off and then back on if it was on when your computer is booted. I.e. see if the problems go away (or perhaps become less bothersome) if you always power the DS on after the computer is running normally.

-Ted


#3
Ted Smith said Howdy Bob

It is intended to be green when a computer is hooked up. What the DS’s USB can really see from the USB line varies a little depending on your USB hardware, including hubs. For example, unfortunately, it isn’t doing an active handshake with a USB driver that could indicate whether an app wanted to talk to the DS.

It is the case that it goes from red to green and back a couple of times as my computer boots or closes down. But being green when the computer is off isn’t something I’d expect.

With an older version of the XMOS code (one not released to anyone out side of PS Audio) I would have the problem that the USB wouldn’t work at all if the DS was on when the computer booted.

On the off chance that your problems are related to something like this, power the DS off and then back on if it was on when your computer is booted. I.e. see if the problems go away (or perhaps become less bothersome) if you always power the DS on after the computer is running normally.

-Ted

Hi Ted,

I’m not sure that I completely understand your answer, but normally I power on the DS (formerly the PWD) from the DS remote after I turn my computer (MacMini) on and it has stabilized. I normally leave the back panel rocker switch of my former PWD on all the time. Of course in the short time that I’ve owned the DS, I’ve had to reboot it a number of times by turning it off and then back on from the back panel rocker switch. Next time that I have to reboot the DS, I will be sure that the computer (MacMini) is on and running normally before rebooting the DS from the rear panel off/on switch.

BTW, after having switched off my system and MacMini for about 1/2 hour, the DS USB light on the front panel remains “green.”

Thanks again and appreciated.

Bob


#4
nordicbob said

Hi Ted,

I’m not sure that I completely understand your answer, but normally I power on the DS (formally the PWD) from the DS remote after I turn my computer (MacMini) on and it has stabilized. I normally leave the back panel rocker switch of my former PWD on all the time. Of course in the short time that I’ve owned the DS, I’ve had to reboot it a number of times by turning it off and then back on from the back panel rocker switch. Next time that I have to reboot the DS, I will be sure that the computer (MacMini) is on and running normally before rebooting the DS from the rear panel off/on switch.

BTW, after having switched off my system and MacMini for about 1/2 hour, the DS USB light on the front panel remains “green.”

Thanks again and appreciated.

Bob


It sounds like you’re doing what I suggest. It’s a pain in the neck to turn things on and off over and over. I’ve only had to turn my DS off to fix something a handful of times. (Well otherwise we would have fixed it.) I’ve been working with Dave and Alex to get to the bottom of this. The fact that it’s staying green could be a hint (I hope.)

#5
Ted Smith said
nordicbob said Hi Ted,

I’m not sure that I completely understand your answer, but normally I power on the DS (formally the PWD) from the DS remote after I turn my computer (MacMini) on and it has stabilized. I normally leave the back panel rocker switch of my former PWD on all the time. Of course in the short time that I’ve owned the DS, I’ve had to reboot it a number of times by turning it off and then back on from the back panel rocker switch. Next time that I have to reboot the DS, I will be sure that the computer (MacMini) is on and running normally before rebooting the DS from the rear panel off/on switch.

BTW, after having switched off my system and MacMini for about 1/2 hour, the DS USB light on the front panel remains “green.”

Thanks again and appreciated.

Bob

It sounds like you’re doing what I suggest. It’s a pain in the neck to turn things on and off over and over. I’ve only had to turn my DS off to fix something a handful of times. (Well otherwise we would have fixed it.) I’ve been working with Dave and Alex to get to the bottom of this. The fact that it’s staying green could be a hint (I hope.)


Thanks Ted. Yes, I am doing like you suggest. I really appreciated all that you, Alex, and Dave are doing to get to the bottom of this. I also appreciated the great communication on the updates from Alex.

Bob


#6

Hi Ted.

As a follow-up, yesterday evening I had my XLO burn-in track on repeat and the DS was playing it over and over like it should. I went out to dinner and when I came back home I found that the DS USB display was “red." The DS somehow lost the signal from my MacMini and it was no longer getting my XLO burn-in track despite my MacMini still showing it as playing. I then changed inputs on my DS remote quickly from USB to another input, I2S I believe, and then back to USB. After doing that the USB light then changed from “red” to “green” and the music suddenly started playing again.

As an experiment, last night I disconnected my USB cable from the DS and left the DS on all night. Even though the USB cable was disconnected, the USB display light remained green all night. It shouldn’t do that, right?

This morning I reconnected the USB cable to the DS, turned on my MacMini, preamp, and amp and then cued up an album from my iPad. Without having to reboot the DS, the music started playing immediately. This is the second time that the DS played music without me having to reboot it and change settings in my System Preference and Midi. However there seems to be no consistency in whether the DS can play music without rebooting from the rear panel off/on switch.

I hope that this follow up info helps in solving my problem.

Thanks,

Bob


#7

Thanks for the further information.

Ironically the FPGA monitors all inputs including the USB no matter what input is selected - i.e. the USB hardware doesn’t know what input is selected, so switching away and back changing the green light status points more to the display board than anywhere else - not that that explains anything.

You are correct that pulling the USB cable should turn the light from green to red. With the USB cable pulled but with the green light on, does the display also show a particular sample rate/bit width, etc or are they a bunch of "-"s?

I don’t think anyone will be in at PS Audio who can further help this weekend, but Alex or Dave will get hold of you on Monday with something.


#8

Hi Ted,

Right now I am listening to 16/44.1 and indeed the DS display reads “PCM Rate 44.1k 16 Bits.” I just pulled the USB from the DS and the display read a bunch of "-"s. I then put the USB cable back into the DS and cued up the same track again and the DS display again reads 44.1k 16 Bits and plays. Everything is behaving perfectly now and sounds great too. BTW, this time when I pulled the USB cable from the DS, the USB display on the DS turned “red” and then “green” again when I reinserted the cable. Strange. It appears to have a mind of its own?

Again thanks!

Bob