How do I fix choppy RX audio?

KEV31779

Hello. I just got my flex 6400 over the weekend. I have the latest version of smartSDR. The problem is when I am listening to a station I will get this audio interruption, stutter and or glitchy audio blips that last about a second or so. It happens every so often but often enough to be annoying. The waterfall seems to be unaffected by this and the headphones are connected directly to the back of the flex. I cannot seem to identify why it is happening or correlate it to anything I am doing wrong. Any help would be nice. I also have an issue when turning on the RX EQ. The audio will seem raspy or over driven. This seems like an independent issue and it does not sound the same as the glitches in the audio. It will be consistent until I turn it off.

Mike-VA3MW

I created a support ticket for this.

73

G0KAD

Same here. Running V3.6.8. Audio from headphones and speaker on the 6400 is fine. PC Audio is broken and choppy. No decodes on most data modes, it's that bad.

KD0RC

Sounds like a network issue. Are you connecting the PC via WiFi? If so, try an Ethernet cable instead and see if that fixes it.

G0KAD

Len, I suspect you're right but the Pc is an i7 connected to the radio by an Ethernet through a router at 1GB/s.

WX7Y

If your running SmartSDR make sure your up to date on the version that is last out.

You can try clicking on "Display" on the Left side of the screen and reduce the "Rate" slider and "FPS" a bit, the Rate slider will make the most difference to the popping due to Network or computer resources.

Just because your computer is a i7 RAM usually the RAM Memory makes a lot of difference especially if your Video card is using part of your system RAM Memory like if your Video is using 4 Gig for the screen graphics there and your computer only has 8 or even 16 Gig total there isn't a lot left so it has to Memory Swap to keep the computer from crashing.

KD0RC

One thing to try if equipment location allows, is to plug the computer directly into the radio (link local). If this clears the issue, then it is likely the router or switch.

You will need to restart the computer and radio for this to work.

I would submit a help desk ticket. Flex Support is very good at solving these kinds of issues.

Mike-VA3MW

The issues you're experiencing with audio quality, such as broken sound, clicks, and dropouts, are symptomatic of a problem, but they do not originate from the radio itself. Instead, these issues are likely rooted in the transport layer of your network. Conducting the test recommended by Len is a valuable diagnostic step.

Your network configuration could be contributing to these problems. Although WiFi is commonly used for streaming applications where minor delays are tolerable, it is not as reliable for applications where real-time data transmission is critical. The nature of WiFi can introduce latency and instability that could affect your radio's performance.

Additionally, the quality of network switches can vary significantly. While most switches facilitate network traffic, some are designed to handle data more efficiently, minimizing issues like flapping (rapidly fluctuating connections) or overrun (data packet loss due to buffer overflow).

Another factor to consider is the physical condition of your network cables. Over time, cables can degrade, impacting their performance. This is not just limited to visible wear; internal wire damage can also occur. Similarly, RJ45 connectors, just like coaxial cable connectors, can suffer from corrosion, which impedes signal quality and reliability.

johnn1jm

What is a good switch to use without breaking the bank?

John N1JM

KD0RC

Hi John, I have been using the NetGear GS-308 successfully. It is an 8 port unmanaged gigabit switch. Goes for a little over $20 USD on Amazon.

I had it well before I ever got my Flex 6400 in 2020. Has worked flawlessly with the Flex.

johnn1jm

Thanks, Len. My switch is a Netgear but I'm not sure of the model number. I haven't been having problems, but I don't want any in the future.

73,

John N1JM

KEV31779

I started this post a year ago. The problem turned out to be the apple settings inside of the PF sense router I was running. Turned off all that apple network garbage and it worked fine. I didn't even know it was on by default.

73

W1KPM

John KB4DU

For unknown reasons, often a 100 Mb switch performs better with a flex than1gig switch.

Conny

https://en.wikipedia.org/wiki/Duplex_mismatch

You will experince collisions and packet loss.