choppy/robotic call quality

[turtlebud]

I've been having some consistent call quality issues lately and need some help troubleshooting the root cause. The main issue on my end - the audio sounds tinny/robotic/choppy.

I ran a phonepower speedtest and generally, one of the datapoints comes back yellow or red, though it fluxuates from test to test. I'm on Comcast with a 50/5 connection, though the VOIP test clocks my download/upload much slower. My setup is: SB6141 --> airport extreme --> ooma

Speed test statistics
---------------------
Download speed: 16908 kbps
Upload speed: 3577 kbps
Download consistency of service: 90 %
Upload consistency of service: 51 %
Download test type: socket
Upload test type: socket
Maximum TCP delay: 124 ms
Average download pause: 2 ms
Minimum round trip time to server: 23 ms
Average round trip time to server: 73 ms
Estimated download bandwidth: 79533 kbps
Route concurrency: 4.703793
Download TCP forced idle: 91 %
Maximum route speed: 22795 kbps

VoIP test statistics
--------------------
Jitter: you --> server: 3.72 ms
Jitter: server --> you: 0.39 ms
Packet loss: you --> server: 1.2 %
Packet loss: server --> you: 0.0 %
Distribution Loss: you --> server: 2.0 %
Distribution Loss: server --> you: 0.0 %
Packet discards: 0.2 %
Packets out of order: 0.0 %
Minimum round trip time to server: 22 ms
Average round trip time to server: 24 ms
Maximum round trip time to server: 32 ms
Round trip time consistency to server: 68 %
Estimated MOS score: 2.9

Where do I start looking?

[murphy]

There should not be any packet loss. In my case my modem, on Comcast, was losing up to 17% of the upstream packets. A new modem took care of the problem.

[domm]

I can not help you with your problem but maybe you can help me with mine. I am trying to do a test using the phonepower site but no luck. A message appears saying I need java. I downloaded & installed java but still no luck trying the phonepower test. Can you suggest a resolution? Thanks

[TonyW]

Here's an HTML5-based alternative:

http://www.whichvoip.com/voip-test-html5.htm

[domm]

Thanks TonyW

[turtlebud]

@murphy, the modem is 2 months old (just start up service with comcast), so it's is past the return period. Is this a defect with the modem and possibly covered by warranty? Is it something that comcast can diagnose and confirm the issue with the hardware?

Thanks!

[murphy]

If you are renting the modem from Comcast, just tell them you want a replacement. In my case it was a personally owned Linksys modem that was a few years old. I replaced it with an Arris modem.
If you own your modem, Comcast is not involved. It's between you and the modem manufacturer.

[turtlebud]

i purchased the modem from bestbuy. it's an arris SB6183. is packet loss something that one can typically request a replacement as defective from the manufacturer? is there any other troubleshooting that I can do before replacing the modem?

[murphy]

Log into the modem at

http://192.168.100.1/

and get the downstream and upstream power levels and the SNR (Signal to Noise Ratio.

Are the uncorrectable counters greater than zero?

[turtlebud]

all the uncorrectables are zero from what I can tell. Here is what I see.