Audio delay on Maestro receive of around 0.5 seconds

Steve Killeen

I am testing my new 6600 and Maestro. I notice that the receive audio of a CW signal on the Maestro is delayed by around 500 ms or so. This happens when connected with my local network to the 6600 and also via Smartlink. 

I tested the TX on CW and all is fine with no delay when listening to the sent signal on an Elecraft K3.

How can any CW operator participate in a contest with such delay ! It's going to be hard to hook up on a signal before anyone else with such a handicap.

Would like to hear from others if they have this problem with their Maestro.

This is very annoying receiving one or two cw letters late !

Here's what I have:
- Flex 6600 (new since a week)
- Maestro (new since a week)

Thanks

Steve WU3I

I have the same problem on Phone listening an online SDR to help extend my RX during net time I hear the SDR audio before the Flex audio on my Maestro.  Only diference is I am 1000 miles remote from Home in Philadelphia in Florida.  SDR is in Far NE Pa.

Steve Killeen

Thanks for the reply. It sure is annoying seeing how much we paid for this console.

ctate243

what are your rx filter widths set too?  brick wall=higher latency.. more relaxed=lower latency.  Latency is an issue with SmartLink but bandwidth is dramatically reduced to make remote more achievable from modest Internet connections. A local network connection is less restrictive and should have measurably less latency. 500ms on a lan seems high to me..  how is your latency plugged directly into the transceiver?

Steve Killeen

I'm using 250 hz with CW. 

Locally I have the Maestro plugged in the same switch as the 6600. Latency should not be a factor !

What do you mean by "how is your latency plugged directly into the transceiver?" Can you explain this ? If I plug my Maestro directly in the LAN port on the 6600, then I cannot fire up SMartSDR on my computer and connect to the 6600 to compare audio latency between the Maestro and 6600.

Thanks

ctate243

Sure .. plug your maestro directly into your transceiver

ctate243

Btw I was referring to your filter settings in radio setup, are they set to lower latency? Is usually use the second setting from left or almost lowest latency

David

Part of the delay is the network Steve and part is the processing required to do the SDR.  One can look at the screen for an update to view the latency and get a real time.  But you can't really appreciate the whole delay without doing a few extra things, like listen to your transmitted Flex signal with a non-SDR radio and get an idea on how long it takes to hear yourself.  That is real world.  There is another way you can test this Steve in order to further demonstrate computer processing delay.  Set up your K3 to transmit with your keyer.  Feed the audio into your computer sound card and do not listen to the radio sidetone.  You should be able to hear a delay.  I can with my 890s and it might be challenging to use the soundcard audio as the only source for the sidetone.  You are not the first person to comment on long times.  You should also note that any setting you choose that alters the receive, like NR, etc will also take processing time.  Personally, my biggest beef with remote operation comes with CW transmit.  My callsign ends in M and stations constantly mistake this for TT.  I have been doing remote operation for over 20 years.  I am not paid to state this but it is my opinion that the Maestro/6600M combination, while not perfect, is the best solution to the problem that I have found so far.

Steve Killeen

It is set completely to the left. Is this OK ? Actually it is set to AUTO !

ctate243

Yes in non contest conditions. That is wide skirt low latency

ctate243

Turn off auto

ctate243

I suspect a network issue of some kind then

Steve Killeen

Thanks for the help Chris.  I did try this on two different networks in two different homes.

Tim - W4TME

We are aware of the issue where the Maestro is experiencing delays related to audio processing and synchronization with the spectrum display.  Our engineering team is working on characterizing the issue to determine if the issue is hardware, software or a combination of both.  In order to fix any type of defect, the first step is to determine the root cause of the issue. Our engineering team is working on the determination of the problem.  I can also tell you that this particular issue does have a high criticality level.

Steve Killeen

Thanks for the update Tim.

Sam Sunny

Any news on this issue? I have a new 6400 with Maestro and i am really disappointed of the delay coming from DAX. The delay is on Maestro and Windows and can´t be normal. Other SDR-Systems like Expert have no noticeable audio delay. I´m using this moment Mac OS and dogpark without any delay so the problem must be the Windows DAX. I had to plug my headphones on the 6400 because the audio delay coming out of the Maestro drives me crazy... Believe me, i´m really thinking about to ship back everything, nearly 4k EUR for a system that cannot be used as described... 
And FYI, i tested everything possible, it´s not the network, not the PC, not any setting, not Windows. 73

Ignacy

Steve,
I sympathize with you as I have a similar Maestro. It has a delay (0.7-1s) whether remote or locally connected via the Ethernet. The delay affects all controls, e.g., changing AF gain takes same time. Flex customer support logged the delay in Oct 2019 as software defect. Have not heard from them since.

It seems that some Maestro owners have this problem and some don't. Maestro uses an old Dell tablet and either some programs are loaded wrong or some of the accessories are defective.

My Surface laptop also has a 0.5 s delay even if connected directly. My 2012 Dell is OK.

Ignacy NO9E

Tonno Vahk

Hi, I am fairly sure all Maestro owners have this delay but for some it is OK and they don't mind or notice. I was testing the delay throughly and there is absolutely no difference if the Maestro is connected straight with good CAT cable to Radio or operated remote over poor internet and Smartlink. It has absolutely nothing to do with network quality.

Here is the video showing the delay (transmitting on another Radio and listening on a Maestro which is connected directly to Radio):

https://www.dropbox.com/s/rojrzh1634kocrx/IMG_7317.mov?dl=0

Depending on Filter setting (Low Latency vs Sharp filters) the delay is indeed between ca 0.6 seconds to 0.9 seconds and makes any serious contest operation completely impossible. And the same is true about SmartSDR on Windows, the same delay when listening PC Audio. I have not tried SmartSDR for MAC.

Interesting to note that band scope has no delay - signals on waterfall and band scope are in real time, only audio is horribly delayed. And when Audio is taken directly from Radio there is almost no delay (small delay though with MAX filters - maybe 0.1-0.15 sec which is tolerable).

Flex opened a ticket based on my reports and I hope they will figure something out.

73

Tonno

ES5TV

Ignacy

Some guys are using Maestro for contesting and this would not work with delays. Some stated explicitly that there is no delay. So there must be something with Maestros that is different.

AWe

As Tim said long time ago:
---
We are aware of the issue where the Maestro is experiencing delays related to audio processing and synchronization with the spectrum display. Our engineering team is working on characterizing the issue to determine if the issue is hardware, software or a combination of both. In order to fix any type of defect, the first step is to determine the root cause of the issue. Our engineering team is working on the determination of the problem. I can also tell you that this particular issue does have a high criticality level.
---
The problem is Windows DAX and it´s unbelievable that this cannot be solved or takes years of research. This is NOT normal and not only a problem on the Maestro. It´s also on a 6-core Intel PC with Windows 10. Just open DAX Audio, listen to it and compare to the direct audio output of the Flex. 0.5-1 sec lag, wheeling over the band is a pain, doing SSB with Maestro or Windows is very bad because of the long lag.
I have to use MAC and iPad, Marcus´s software is great with low lag, also Don´s DPSDR which is absolute great as for lag. BUT i have an Maestro that i will use...
Tim, are there any news or a new software that i can test?

Tonno Vahk

Yes, I can also confirm now after testing that it is Windows issue. Even on my I Phone with SmartSDR connected over Smartlink and poor 4G the delay is very small and nothing like Maestro or Windows PC.

ES5TV

N2TTA

This why i still use Remoterig for audio and CW

N2TTA

Tonno Vahk

I did purchase SmartSDR for Mac. It works beautifully with very small delay, just like the 6600M itself. So from my side it is fully confirmed now that the delay is fully a Windows issue. Thus the only way to do remote contesting seriously currently is with Apple devices. Till Windows issues get fixed. Many other nice features there in SmartSDR for Mac, looks very nice and promising.

73

ES5TV

AWe

Yes, i use also Mac´s and IPad and i can also confirm it´s fine to use Flexradios on Apple Devices. It´s a shame that so many users must live with this terrible delay in Windows/Maeestro and no one from Flexradio cares about this.

I used in the past ExpertSDR on Windows and Mac and there was never a delay.

73

hb9tsw

I made several tests and I fully agree about the Windows audio latency.
I use Flex-6400, linked over a 6km 5GHz WiFi LAN, with Maestro. Not a jocke of investment for owning a radio system that in not usable at all, despite the promises of that guy at Friedrichshafen Messe on how fast is QSK over LAN. I mean, dou you guys try things before selling them at FlexRadio?
It is a grat receiver, a powerful tool, but this audio latency is just disappointing.

ka9ees

I have to admit. Once I started using my new iPad. I put the Maestro and the Windows 10 laptop away. This iPad is like sitting in front of the rig. But, I’m only a casual rag chewer.

73,

Ed KA9EES

DL4RCE

I do use the Maestro but have Audio/PTT directly connected to the 6600. That works well but wonder how I will do it when having the 6600 on a remote location :/

Volker

George-SV9DJO

Hi ,
Maestro is great for smartcontrol and rag chewing.Forget contesting even with PC sound card as well.\nI tried with ASIO low latency sound cards with better result but still not as expected ,\nThe best way to run in contest with minimal latency is with iPad (or MAC with smartsdr for maos) for audio ,maestro for smart control and pc for logging software.\nIf you running remote choose you can save some msec by using layer2 VPN (openVPN L2,mikrotik BCP or EoIP) than smartlink. I will post soon a How to guide for easy implementation of the above. 73 George SV9DJO \n\n"}]

Ignacy

I second the experience of Volker. Long delay in my Maestro with audio output to Maestro. Short delay with audio sent to 6600.

Same with the PCs. Long delay playing via PC audio and short playing through the radio.

Ignacy, NO9E

WX7Y

I got tired of the Delay's, Audio Popping and and the other BUG's built into version 3, and V2.5 SmartSDR so I went back to 2.4.10 and it took care of those issues BUT I sure miss Multilink that is built into Version 3.

Hope they got those things fixed pretty soon.

John, G3WKL

Just measured the audio delay between a dah sent by a KX3 and the received dah on the Maestro. I got a delay of 560mS for a direct Ethernet connection, and 552mS when the Flex was connected via Ethernet to the router and the Maestro connected to the router via WiFi. I suspect that the difference is measurement error in my placement of the cursors on the 'scope.

The KX3 trace (the upper one in the photo) is of the audio sidetone and the lower trace is the audio from the Maestro.

IMG_20210210_123420.jpg

The filters in the Maestro were set to their lowest latency, and the network latency(RTT) was just a few mS in both cases. Using v2.6.2 and one of the original Maestros 0516-5092-0100-0044

Using the same method I measured the delay of the audio from SmartSDR (and the KX3 transmission) as 60mS - some of this could be the difference between the timing of the sidetone and actual RF coming out from the KX3

I note that Tim, W4TME, commented last March that this was seen as 'high criticality level', but I'm just wondering how work is progressing to address this issue

73 John, G3WKL