TOPIC:

Hi all,

I am using my Flex Balanced for over a week now and really like it. I was able to do measurements and get the speakers x-overs done etc. I used REW and played the sweep through the USB audio input on the Flex. Nice and easy.

For the life of me, i can't get REW to work anymore this way. I tried about everything (i think) but i cannot get any sound from my Mac played through USB to the Flex. Not through REW, not even 'normal' audio using Spotify, VLC Player etc etc. I can access the Flex through USB and all other inputs (optical,spdif) work fine.  The Flex shows up in the Midi Setup and in other applications as well.

Any hints? I hope it's something I am missing.

Thanks,

Stefan

Edit: I'll try a different Mac tomorrow to exclude that from the equation.

I tried another Mac - exactly the same result as described below.

Stefan

I disconnected the power last night and tried again this morning. Works fine now. Go figure.

Hi Stefan,
I have the flex digital version that I tested first on my office computer (PC windows 10) It works via USB input for a couple of days and then sudently, no sound anymore through USB input. The only way I've found so far was, as you did, to disconnect and reconnect the power supply of the Flex to get the sound back ! So it is not related specifically to mac but windows OS too.
A reboot of the computer and or an unplug of the USB cable did not change anything. The only solution to recover the sound was to disconnect Flex power and reconnect it.
It is very bothering...
Then, last week I moved the flex to another computer and since then, it works ok there. SO what can we deduct ?
- it is a bug related to flex hardware
- it will be hard to track it down as it seems to be hardware dependant
Looking forward to minidsp team suggestion...
Jean Claude

Hi All,

Same problem here, except there's never sound using the USB input. Laptop detects the Flex no issue. (Un)power the Flex didn't help.
Otherwise everything works fine, but missing the point somewhat when USB audio isn't possible.

Update 24-07-22: After contacting MiniDSP support, they continuously adviced the source selection was set wrong (not set to USB). However, it was always set to USB, but no sound. My solution was to unplug the Flex from power, attach the USB cable to Flex and laptop, then switch on the laptop and then power the Flex, and it worked. There was never a problem with the Flex PEQ interface, only when trying to play music or soundfiles from the laptop or REW.

I should have added firmware 1.21/1.25 loaded...

I have issues with my miniDSP Flex Balanced USB audio as well. Occasionally, the unit won't play sound via USB. I used two sources so far: windows 10 PC and an iPhone. At first I thought it might be a cable issue, but then I tried two more cables, including the one which was shipped with the unit.
Turning off the unit, detaching the power cable and waiting for more than few dozens of seconds and then turning the unit on helps to get the USB audio work again. I don't know exactly what causes the issue, but I think that it has to do with the fact that I am switching between different USB audio sources.

Having to power of the unit after attaching another USB source is a bit annoying. Moreover, I hope the USB audio won't eventually stop working.

Same FW here.

I had the same issue again today. I was doing some measurements using REW through the USB input. While looking at a tutorial on youtube, the sound suddenly cut out (the sound from the video was playing over my speakers). I am not sure, but it may have happened when the display of the Flex went in powersave/dark.

I will try this scenario again tomorrow, would be good if it can be reproduced so that it can be fixed, hopefully.

Satefan

That would be interesting. 👌

So, i still was not able to play music over USB - i could connect to the unit with the DSP application and control the unit, but no music. I disconnected power, waited for 30 mins or so and tried again. It played music though USB right away.

I waited for the display to go black, and the music kept playing, so that's not the issue. It was a bit of a long shot of course.

I cut a ticket with MiniDSP to see if there is anything that can be done.

I'll keep this post updated based on the outcomes.

Cheers.

Satefan

Here is the reponse on my question from MiniDSP:

"in 99% cases we see for such issue, it relates to a USB cable that is longer than the specs. Max length is 2-3m for USB audio high speed. Is that possible that you're using a longer USB cable? "

Initially, this was the case indeed. But not recently. I'll avoid using the longer cable and buy a good quality USB cable. I have had issues in the past with my Umik-2 and a dodgy USB cable, replacing it by a decent cable solved the issue.

Cheers,

Satefan

Thanks for updating. Quite an interesting reply from support pointing to 99% (user)error by wrong USB (length) cable. Sure.

However, I'm using a (professional) shielded USB bi-directional USB cable, length 3 meter (about 10 ft). Recommended lenght for a USB cable is 4 to 5 meter to avoid signal loss, so I'm well under that. My other equipment never showed this issue. 

The supplied USB cable from MiniDSP is much, much shorter and showed the same issue. Does MiniDSP ship out inferior USB cables? 

Imo, there is an issue with the USB port in the MiniDSP Flex, where it only (re)connects (or resets), when power is cut. The thing is, The MiniDSP software PEQ interface always work, just not sending sound.

​I have to switch off al gear, connect the USB cable, switch on the Flex and laptop. Then it works. Sometimes I have to remove the power from the Flex to get it going.

I have a very hard time believing this is the USB cable as I tried multiple good quality cables with the same outcome, well under 4 meter (12 ft).

I also contacted support and their response was that I probably didn't switch to USB on the Flex, although I explained carefully. I didn't continue with support, because I have a workaround and I didn't feel they did a serious job in helping in figuring it out (or taking the issue seriously). They where friendly, that's all I can say. 



 

I am skeptical as well. However, I was using a USB extension cable when i ran in to issues. I will try without this for a bit and see if it improves.

Controlling the MiniDSP through the USB connection does not require much bandwidth over the USB link. Streaming 192khz 24bit is a different story of course. With my UMIK-2 mic, i had to get a high quality cable (compared to my Umik-1) as the additional bandwidth required exceeded the ability of the el-cheapo USB cable i used initially.

I'll post updates if there are any.

Cheers,

Satefan

I'm surprised as well by the team answer (99% due to USB cable) I had the same problem with high quality short USB cable (less than 1 m) I have two other USB streamers working flawlessly with these cables.
I would suggest to miniDSP team to reconsider their position and seriously investigate the USB software/firmware part of the Flex series