6300 random pops and crackles during digital TX

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My 6300 pops and crackles while transmitting digital signals (DAC). I'm not using Remote. The radio and computer is wired through a gigabit switch and lan. All Ethernet cables have 31 mix ferrites on both ends. I can hear the pops and crackles with the monitor selected and also see the pops and crackles on the waterfall. With the waterfall display turned on during TX they look like horizontal spikes. Since I do not have another SDR receiver I'm unable to verify if these noises are actually going out over the air however I suspect they are. The radio has so many nice features and I enjoy running JT65, JT-9, PSK modes but I'm very unhappy with these random annoying sounds. This is not what I would expect out of a "Signature Series Radio" !
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Cal Spreitzer

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Posted 3 years ago

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George Molnar, KF2T, Elmer

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Can you describe your computer setup? Frequently these kind of issues are related to computer/OS resources. Are you using DAX, or an external interface?
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Cal Spreitzer

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Hi George,

Intel Core I7-960 Quad Core Processor@ 3.2 GHZ
ASUS Rampage III 6gb/sec USB 3.0 Motherboard
256 GB Crucial Real SSD SATA III/MLC Solid State Drive
Kingston HyperX 16GB DDR-3 1600 Memory
ASUS GeForce GTX460 1 GB/256 bit PCI Express Video Card.
Windows 7 64-bit Home Premium.

I'm using DAX. The computer and 6300 are connected to a gigabit switch (wired). The switch is connected to my gigabit router. I've seen this issue since Nov 2014 when I first purchased the 6300 direct from flex.

Cal / N3CAL
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Steve N4LQ

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The random pop problem in the 6300 has been noticed since day 1 but only on CW. There are several threads to this effect. When using QSK on CW it shows up as a loud pop with no particular pattern. It may be visible but the screen is really too busy to notice.
Flex's response has been....."Yes we know about it and it affects all models and will be addressed in software updates."  However from my and other's experience this type of pop only happens with the 6300 and seems hardware related as if something is building up then discharging. 
My 6500 is totally clean. No artifacts like this at all. If Flex can fix this I would buy another 6300 for the other shack. 
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Cal Spreitzer

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Well the issue is also on digital modes (DIGU).  I also was able to confirm the noises do go out over the air.  I have an RT USB dongle receiver and can see and hear the distortion using a separate computer/RT Dongle Receiver.   

Cal/N3CAL 
(Edited)
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Tim - W4TME, Customer Experience Manager

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I recommend using LatencyMon to test your PC to see if it is suitable for processing real time audio via DAX.  https://helpdesk.flexradio.com/hc/en-us/articles/202118698-Using-LatencyMon-to-collect-DPC-Latency-D...
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Cal Spreitzer

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Hi Tim,

Okay I downloaded and ran Latency Mon.  I was surprised to receive the following results:  (What would you recommend I do next? ) 
_________________________________________________________________________________________________________
CONCLUSION
_________________________________________________________________________________________________________
Your system appears to be having trouble handling real-time audio and other tasks. You are likely to experience buffer underruns appearing as drop outs, clicks or pops. One or more DPC routines that belong to a driver running in your system appear to be executing for too long. Also one or more ISR routines that belong to a driver running in your system appear to be executing for too long. One problem may be related to power management, disable CPU throttling settings in Control Panel and BIOS setup. Check for BIOS updates.
LatencyMon has been analyzing your system for  0:04:29  (h:mm:ss) on all processors.


_________________________________________________________________________________________________________
SYSTEM INFORMATION
_________________________________________________________________________________________________________
Computer name:                                        N3CAL-CORE-I7
OS version:                                           Windows 7 Service Pack 1, 6.1, build: 7601 (x64)
Hardware:                                             ASUSTeK Computer INC., Rampage III GENE
CPU:                                                  GenuineIntel Intel(R) Core(TM) i7 CPU 960 @ 3.20GHz
Logical processors:                                   8
Processor groups:                                     1
RAM:                                                  16375 MB total


_________________________________________________________________________________________________________
CPU SPEED
_________________________________________________________________________________________________________
Reported CPU speed:                                   3238.0 MHz
Measured CPU speed:                                   3752.0 MHz (approx.)

Note: reported execution times may be calculated based on a fixed reported CPU speed. Disable variable speed settings like Intel Speed Step and AMD Cool N Quiet in the BIOS setup for more accurate results.


_________________________________________________________________________________________________________
MEASURED INTERRUPT TO USER PROCESS LATENCIES
_________________________________________________________________________________________________________
The interrupt to process latency reflects the measured interval that a usermode process needed to respond to a hardware request from the moment the interrupt service routine started execution. This includes the scheduling and execution of a DPC routine, the signaling of an event and the waking up of a usermode thread from an idle wait state in response to that event.

Highest measured interrupt to process latency (μs):   6855.439171
Average measured interrupt to process latency (μs):   2.785272

Highest measured interrupt to DPC latency (μs):       1976.040899
Average measured interrupt to DPC latency (μs):       1.025622


_________________________________________________________________________________________________________
 REPORTED ISRs
_________________________________________________________________________________________________________
Interrupt service routines are routines installed by the OS and device drivers that execute in response to a hardware interrupt signal.

Highest ISR routine execution time (μs):              2012.333848
Driver with highest ISR routine execution time:       nmserial.sys - Serial Device Driver, Windows (R) Win 7 DDK provider

Highest reported total ISR routine time (%):          0.109949
Driver with highest ISR total time:                   dxgkrnl.sys - DirectX Graphics Kernel, Microsoft Corporation

Total time spent in ISRs (%)                          0.144607

ISR count (execution time <250 μs):                   449983
ISR count (execution time 250-500 μs):                0
ISR count (execution time 500-999 μs):                0
ISR count (execution time 1000-1999 μs):              13
ISR count (execution time 2000-3999 μs):              1
ISR count (execution time >=4000 μs):                 0


_________________________________________________________________________________________________________
REPORTED DPCs
_________________________________________________________________________________________________________
DPC routines are part of the interrupt servicing dispatch mechanism and disable the possibility for a process to utilize the CPU while it is interrupted until the DPC has finished execution.

Highest DPC routine execution time (μs):              3902.319024
Driver with highest DPC routine execution time:       dxgkrnl.sys - DirectX Graphics Kernel, Microsoft Corporation

Highest reported total DPC routine time (%):          0.057148
Driver with highest DPC total execution time:         USBPORT.SYS - USB 1.1 & 2.0 Port Driver, Microsoft Corporation

Total time spent in DPCs (%)                          0.261670

DPC count (execution time <250 μs):                   2438904
DPC count (execution time 250-500 μs):                0
DPC count (execution time 500-999 μs):                0
DPC count (execution time 1000-1999 μs):              26
DPC count (execution time 2000-3999 μs):              1
DPC count (execution time >=4000 μs):                 0


_________________________________________________________________________________________________________
 REPORTED HARD PAGEFAULTS
_________________________________________________________________________________________________________
Hard pagefaults are events that get triggered by making use of virtual memory that is not resident in RAM but backed by a memory mapped file on disk. The process of resolving the hard pagefault requires reading in the memory from disk while the process is interrupted and blocked from execution.


Process with highest pagefault count:                 firefox.exe

Total number of hard pagefaults                       14
Hard pagefault count of hardest hit process:          11
Highest hard pagefault resolution time (μs):          281.313774
Total time spent in hard pagefaults (%):              0.000017
Number of processes hit:                              3


_________________________________________________________________________________________________________
 PER CPU DATA
_________________________________________________________________________________________________________
CPU 0 Interrupt cycle time (s):                       4.435296
CPU 0 ISR highest execution time (μs):                2012.333848
CPU 0 ISR total execution time (s):                   0.438970
CPU 0 ISR count:                                      287398
CPU 0 DPC highest execution time (μs):                1954.186844
CPU 0 DPC total execution time (s):                   2.656696
CPU 0 DPC count:                                      1846621
_________________________________________________________________________________________________________
CPU 1 Interrupt cycle time (s):                       1.064388
CPU 1 ISR highest execution time (μs):                15.933910
CPU 1 ISR total execution time (s):                   0.059572
CPU 1 ISR count:                                      6396
CPU 1 DPC highest execution time (μs):                47.042001
CPU 1 DPC total execution time (s):                   0.066632
CPU 1 DPC count:                                      8386
_________________________________________________________________________________________________________
CPU 2 Interrupt cycle time (s):                       5.272699
CPU 2 ISR highest execution time (μs):                1992.042619
CPU 2 ISR total execution time (s):                   2.372626
CPU 2 ISR count:                                      116442
CPU 2 DPC highest execution time (μs):                3902.319024
CPU 2 DPC total execution time (s):                   1.424055
CPU 2 DPC count:                                      271550
_________________________________________________________________________________________________________
CPU 3 Interrupt cycle time (s):                       0.938822
CPU 3 ISR highest execution time (μs):                0.0
CPU 3 ISR total execution time (s):                   0.0
CPU 3 ISR count:                                      0
CPU 3 DPC highest execution time (μs):                0.0
CPU 3 DPC total execution time (s):                   0.0
CPU 3 DPC count:                                      0
_________________________________________________________________________________________________________
CPU 4 Interrupt cycle time (s):                       1.598147
CPU 4 ISR highest execution time (μs):                0.0
CPU 4 ISR total execution time (s):                   0.0
CPU 4 ISR count:                                      0
CPU 4 DPC highest execution time (μs):                38.930204
CPU 4 DPC total execution time (s):                   0.210481
CPU 4 DPC count:                                      61441
_________________________________________________________________________________________________________
CPU 5 Interrupt cycle time (s):                       0.869378
CPU 5 ISR highest execution time (μs):                162.913527
CPU 5 ISR total execution time (s):                   0.004737
CPU 5 ISR count:                                      851
CPU 5 DPC highest execution time (μs):                45.339098
CPU 5 DPC total execution time (s):                   0.006486
CPU 5 DPC count:                                      967
_________________________________________________________________________________________________________
CPU 6 Interrupt cycle time (s):                       1.056189
CPU 6 ISR highest execution time (μs):                10.058987
CPU 6 ISR total execution time (s):                   0.023277
CPU 6 ISR count:                                      4988
CPU 6 DPC highest execution time (μs):                1964.679432
CPU 6 DPC total execution time (s):                   0.172132
CPU 6 DPC count:                                      14199
_________________________________________________________________________________________________________
CPU 7 Interrupt cycle time (s):                       2.926583
CPU 7 ISR highest execution time (μs):                13.205683
CPU 7 ISR total execution time (s):                   0.221337
CPU 7 ISR count:                                      33922
CPU 7 DPC highest execution time (μs):                1923.938542
CPU 7 DPC total execution time (s):                   1.110198
CPU 7 DPC count:                                      235767
_________________________________________________________________________________________________________
(Edited)
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Steve N4LQ

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Plug the rig directly into your computer's nic card and see if it still pops. 
This is entirely a different problem than the CW pops.
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Tim - W4TME, Customer Experience Manager

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Thanks for the LatencyMon report.  Your DPC latency (almost 4000 uS) is way too high for real-time audio streaming and the hardware that is causing the problem is your video adapter.  You need to have DPC latency less than 1000 uS and you should target for 100s of microseconds.  

Until you get the DPC latency below 500 uS, you are going to continue to have these issues when running DAX.

I recommend you do the following.  First update your PC BIOS to the latest version.  Second, update your video drivers to the latest version.  Third, update your ASUS motherboard's chipset drivers; I would get the ones from Intel for the Intel X58 and Intel ICH10R southbridge chipsets.

You also have a MosChip PCI parallel/serial port card installed in your PC and this device is responsible for long ISR times.  I would see if there is an updated driver for that hardware too.
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Cal Spreitzer

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I've done some more BIOS tweaking and have gotten better results.  I can notice an improvement while transmitting. There are hardly no pops or crackles now. 

 

Cal/N3CAL
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Tim - W4TME, Customer Experience Manager

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Excellent!  Hunting down and mitigating long duration DPCs is not a trivial task.  Congratulations on your success.
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Cal Spreitzer

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Thanks for the help Tim!  It appears I have all the latest drivers for my motherboard BIOS and Chipset. I removed the PCI parallel/serial port from the machine.  I also updated the Video Card drivers to the latest ones from NVIDIA but sadly I was unable to get the DPC latency down to acceptable levels.  Although it's better than before it's sitting at about 1900 uS.   That's with SSDR, DDutil, DAX, WSJT-X and HRD logbook all running. 

I built this computer about 5 years ago.  It's been a solid performer.   WSJT-X still works and I make and receive contacts just fine but I can see the pops etc.   It might be time to update the mother board/memory/chip but before I do that I may try just updating the video card first.  

Thanks again for the help

Cal/N3CAL

    
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George Molnar, KF2T, Elmer

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Cal, I have been working a similar, but less intense issue. Found that changing my NIC, and running at 100 MB/s helped a good bit. Still not perfect, but better. SSDR doesn't need the full Gb/s even at full tilt.
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Cal Spreitzer

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Thanks for the info George.  I'll put it on my list of things to try. 73

Cal/N3CAL