Livewire audio drops

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fabienfs
Posts: 1
Joined: Wed Dec 26, 2012 11:39 pm

Livewire audio drops

Post by fabienfs »

Hello,

I have a problem in my Livewire network.
I regularly have audio drops of +/- 30ms.
Example : https://soundcloud.com/fabienfs/drop-axia

My config :
- Cisco Catalyst 3560G (WS-C3560G-48TS version 12.2(55)SE7)
- Axia iQ QOR32
- PC Windows 8 with Axia Driver 2.6.1.18 and Intel Gigabit Network Card

Image

The config of my Cisco switch:

Code: Select all

version 12.2
no service pad
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
hostname SwitchBureau
boot-start-marker
boot-end-marker
no aaa new-model
system mtu routing 1500
!
ip igmp snooping querier max-response-time 25
ip igmp snooping querier timer expiry 205
ip igmp snooping querier
!
mls qos srr-queue input buffers 50 50
mls qos srr-queue input cos-map queue 1 threshold 1 5
mls qos srr-queue input cos-map queue 2 threshold 1 6 7
mls qos srr-queue output cos-map queue 1 threshold 1 6 7
mls qos srr-queue output cos-map queue 3 threshold 1 5
mls qos
!
...
!
spanning-tree mode pvst
spanning-tree extend system-id
!
vlan internal allocation policy ascending
!
interface GigabitEthernet0/1
 description WiFi
 switchport access vlan 70
 switchport mode access
!
interface GigabitEthernet0/10
 description Axia PC
 switchport access vlan 40
 switchport mode access
 switchport nonegotiate
 switchport block multicast
 switchport voice vlan dot1p
 srr-queue bandwidth share 30 20 25 25
 srr-queue bandwidth shape 0 0 0 0
 priority-queue out
 mls qos trust cos
 spanning-tree portfast
 no ip igmp snooping tcn flood
!
...
!
interface GigabitEthernet0/16
 description Axia iQ
 switchport access vlan 40
 switchport mode access
 switchport nonegotiate
 switchport block multicast
 switchport voice vlan dot1p
 srr-queue bandwidth share 30 20 25 25
 srr-queue bandwidth shape 0 0 0 0
 priority-queue out
 mls qos trust cos
 spanning-tree portfast
 no ip igmp snooping tcn flood
I notice that if I do file transfers over the network (in other VLANs that LiveWire network), I have a lot more audio drops

Yet my Cisco switch hardly works. Maybe 1% of its resources...

Statistics of my Axia Driver :
Image

How to fix this?

Thanks

Best Regards,
Fabien

kfmk-eng
Posts: 2
Joined: Tue Jul 07, 2015 11:55 pm

Re: Livewire audio drops

Post by kfmk-eng »

We are having a similar problem here in Austin. Within a 15 minute period of recording we caught 4 of these drops. These drop occur all the time. There is no period of logging that I have checked that did not have these drops in it.

I have torn my network apart looking for the root cause. We have the same setup as you. The network hardware is a Cisco 2948G configured to Axia specs per their documentation. My network is running nominally at about 200Mbit. None of the switch ports are logging any errors. I do not believe that my switch is the cause.

I placed my automation on an analog ASI 6640 card and brought it into the Axia via an Analog IO. I wanted to discount my automation system and the Axia IP Audio driver as the culprit. I double punched the analog output and logged it on a separate computer. I had the drop outs on my main VMIX but not on the analog outputs. This confirmed that my drop outs are an Axia issue.

I then took a iProfiler log of the output of my PGM1 bus on my element console and compared that to my main VMIX output to my STL. I found that the PGM1 bus of the board did not have the drop outs and the VMIX output did.

So, at this point I am gearing up to swap my Studio Engine with another one I have on site to see if the problem is in the VMIX. The studio engine is running at around 80% utilization. I have streamlined my VMIX's to get that percentage lower with no avail. The drop outs persist.

I would like to hear if you ever were able to isolate and fix this issue on your network. It would be nice to find that out before I go and swap my gear around.

Thanks!

User avatar
AXIA_milos
Axia Team
Posts: 281
Joined: Fri May 25, 2007 2:54 am
Location: San Luis Obispo, CA

Post by AXIA_milos »

In Fabien's case, the drop outs may be in the input to the PC. The evidence of this is in the RxUr and RxSeqErr.
RxUr is an under run counter, which is a situation where the receiver buffer went empty before another packet was received. This can cause audio break
RxSeqErr is sequence error counter, each packet has a sequence ID and it is expected that the next packet in the stream is one more than the previous. If not, SeqErr. This is evident of dropped packets.

This performance can be due to network issues or windows antivirus software or Firewall software.

User avatar
AXIA_milos
Axia Team
Posts: 281
Joined: Fri May 25, 2007 2:54 am
Location: San Luis Obispo, CA

Post by AXIA_milos »

In KFMK's case, the engine utilization is rather high. Which hardware version of Engine and which software. It is possible the engine isn't able to keep up to the load. In older software versions, the CPU utilization reporting was not able to show peak utilization. At 80%, it is likely the CPU is peaking at 100% occasionally and a lost cycle may occur. Attempt to reduce mic processing on any channels that have them applied to see if this reduces the utilization and the drops.
You can also attempt to reduce amount of inputs into the Engine... or make more of those inputs standard stream over Live stream.

kfmk-eng
Posts: 2
Joined: Tue Jul 07, 2015 11:55 pm

Post by kfmk-eng »

Before I forget: You guys rock. You have been great with the help and I really appreciate it!!

I was wondering about high CPU utilization myself. I can move some of my mixes around to reduce the load on this studio engine. I have 2 engines and the other one is barely used. I have set almost all of the streams for my vmixes to standard stereo as well. This did not have a noticeable effect on the utilization.

I was also wondering if a CPU upgrade to the unit might be in order. The unit takes a Core Duo 2500. The Core2Duo 7500 is a direct drop in replacement. maybe reducing the mixes and upgrading the CPU will help.

Thanks for all the help so far!


AXIA_milos wrote:In KFMK's case, the engine utilization is rather high. Which hardware version of Engine and which software. It is possible the engine isn't able to keep up to the load. In older software versions, the CPU utilization reporting was not able to show peak utilization. At 80%, it is likely the CPU is peaking at 100% occasionally and a lost cycle may occur. Attempt to reduce mic processing on any channels that have them applied to see if this reduces the utilization and the drops.
You can also attempt to reduce amount of inputs into the Engine... or make more of those inputs standard stream over Live stream.

User avatar
AXIA_milos
Axia Team
Posts: 281
Joined: Fri May 25, 2007 2:54 am
Location: San Luis Obispo, CA

Post by AXIA_milos »

I just spoke with the support tech on your case and he will work with you on attempting to reduce CPU. Drop in CPU is not a very common practice. A customer in France did this and I'm not sure how successful that was as they later upgraded to the Fanless Engines. We later saw their original units and they did some tweaking to the BIOS which caused issues for us. We don't have any experience with upgrading the CPU, so if you do so, you will be a little on your own. First lets get the CPU utilization lowered. If we can't, I will suggest looking at upgrade options to the Fanless Engines.

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