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Discussion Starter · #1 ·
Hi,

Since this past weekend, my Spectrum 201 cable box has not been working right with my Onkyo 777.

When plugged into ANY of the rear HDMI ports, the receiver will not play audio from the Spectrum cablebox. Once I plug the cablebox directly to the front AUX HDMI port the audio kicks in.

I've swapped out cable boxes twice, we've soft reset it and the receiver to clear the possibility of a handshake issue, cleared the receiver settings, swapped out HDMI cables, tried other sources into the CBL/SAT HDMI port and everything is good. Spectrum box just doesn't want to play audio when plugged into the rear of the AVR.

Any thoughts?
 

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Hi,

Since this past weekend, my Spectrum 201 cable box has not been working right with my Onkyo 777.

When plugged into ANY of the rear HDMI ports, the receiver will not play audio from the Spectrum cablebox. Once I plug the cablebox directly to the front AUX HDMI port the audio kicks in.

I've swapped out cable boxes twice, we've soft reset it and the receiver to clear the possibility of a handshake issue, cleared the receiver settings, swapped out HDMI cables, tried other sources into the CBL/SAT HDMI port and everything is good. Spectrum box just doesn't want to play audio when plugged into the rear of the AVR.

Any thoughts?
Have you configured the Spectrum box to output a fixed resolution? (e.g. 1080i)

I found that to be much more reliable than letting the output resolution match the channel's resolution. Some of the channels in my subscription are 1080i, some are 720p and some are 480i. As a result, there would have to be a new HDMI handshake almost every time I changed channels. That handshake doesn't happen if the STB's output resolution is fixed. There's still a delay while the STB resynchronizes, but it doesn't affect the HDMI signal.

Has the firmware been updated recently in the cable box, receiver or TV?

Sometimes unannounced firmware updates can break the HDMI/HDCP handshake. For example, DirecTV has been notorious for doing that, although I haven't seen any recent complaints. People had to complain to them whenever that happened so it'd get fixed in the next firmware update.

Even so, you should make sure that the STB, receiver and TV all have up to date firmware.

Are the replacement HDMI cables "Certified Premium"?

They come with a special holographic tag.

Cables with that certification have reduced attenuation and dispersion when compared to non-certified cables, so they don't damage the HDMI signal as much. They help with marginal 1080p or 1080i signals as well as with 4K signals.

FWIW, I don't recall my Spectrum box having this kind of problem since I went to a fixed resolution, but it's connected to an old NR1501 with HDMI v1.3. My impression is that HDMI v2 is much more sensitive to marginal HDMI signals.
 

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Discussion Starter · #3 ·
Have you configured the Spectrum box to output a fixed resolution? (e.g. 1080i)

I found that to be much more reliable than letting the output resolution match the channel's resolution. Some of the channels in my subscription are 1080i, some are 720p and some are 480i. As a result, there would have to be a new HDMI handshake almost every time I changed channels. That handshake doesn't happen if the STB's output resolution is fixed. There's still a delay while the STB resynchronizes, but it doesn't affect the HDMI signal.

Has the firmware been updated recently in the cable box, receiver or TV?

Sometimes unannounced firmware updates can break the HDMI/HDCP handshake. For example, DirecTV has been notorious for doing that, although I haven't seen any recent complaints. People had to complain to them whenever that happened so it'd get fixed in the next firmware update.

Even so, you should make sure that the STB, receiver and TV all have up to date firmware.

Are the replacement HDMI cables "Certified Premium"?

They come with a special holographic tag.

Cables with that certification have reduced attenuation and dispersion when compared to non-certified cables, so they don't damage the HDMI signal as much. They help with marginal 1080p or 1080i signals as well as with 4K signals.

FWIW, I don't recall my Spectrum box having this kind of problem since I went to a fixed resolution, but it's connected to an old NR1501 with HDMI v1.3. My impression is that HDMI v2 is much more sensitive to marginal HDMI signals.
Thanks for your thorough input, i'll try to address each point:
Fixed resolution=NO. I didn't think that was necessary as the video still plays fine, just no audio.

Firmware= No idea. Spectrum/Charter just send updates as they please. Unlike my Oppo, or Xbox, I don't know when an update gets pushed until long after the fact.

HDMI cable= I use these https://www.amazon.com/Mediabridge-...pID=51MCVHnhTaL&preST=_SY300_QL70_&dpSrc=srch on every device in my home with no issues; that's roughly 20 cables

Other than that I feel everything is up and up. Keep in mind the original box played fine, just I exchanged due to other non-audio/unrelated issue. Im now on the 3rd box in two days with no resolution in sight.
 

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Thanks for your thorough input, i'll try to address each point:
Fixed resolution=NO. I didn't think that was necessary as the video still plays fine, just no audio.
Loss of audio or video is one of the symptoms of the HDCP handshake failing. If the HDMI signal is marginal, it can keep failing in exactly the same way.
Firmware= No idea. Spectrum/Charter just send updates as they please. Unlike my Oppo, or Xbox, I don't know when an update gets pushed until long after the fact.

HDMI cable= I use these https://www.amazon.com/Mediabridge-...pID=51MCVHnhTaL&preST=_SY300_QL70_&dpSrc=srch on every device in my home with no issues; that's roughly 20 cables
Nonetheless, I strongly urge that you replace both the cable between the STB and the receiver and the cable between the receiver and the TV by ones which are formally "Certified Premium", including the official holographic certification tag. Here's an example as sold by Blue Jeans Cable: https://www.bluejeanscable.com/store/hdmi-cables/premium-hdmi-cable.htm
Other than that I feel everything is up and up. Keep in mind the original box played fine, just I exchanged due to other non-audio/unrelated issue. Im now on the 3rd box in two days with no resolution in sight.
My understanding is that many of the boxes Spectrum hands out are recycled, though repackaged. They might have been returned because of the problems you report.
 

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Discussion Starter · #5 ·
Loss of audio or video is one of the symptoms of the HDCP handshake failing. If the HDMI signal is marginal, it can keep failing in exactly the same way.

Nonetheless, I strongly urge that you replace both the cable between the STB and the receiver and the cable between the receiver and the TV by ones which are formally "Certified Premium", including the official holographic certification tag. Here's an example as sold by Blue Jeans Cable: https://www.bluejeanscable.com/store/hdmi-cables/premium-hdmi-cable.htm


My understanding is that many of the boxes Spectrum hands out are recycled, though repackaged. They might have been returned because of the problems you report.

What shocks me is that nothing in the chain was changed. Simply from one day to another there is no audio.

IRT the HDMI cable, I have tried multiple ones with no success. The "Premium" certification is for features far beyond what a typical set top box utilize, such as 18gbps, 4K60HZ and BT.2020. I don't feel that would even be a problem, especially since I moved that cable to link my Oppo 4K player and I get full picture, audio, DV, etc … which leads me to believe the cable is NOT the issue.


The part of the recycled box I can totally agree with. I will get them one more shot today. Still strange that it works perfectly with any cable on the front AUX HDMI port...
 

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What shocks me is that nothing in the chain was changed. Simply from one day to another there is no audio.

IRT the HDMI cable, I have tried multiple ones with no success. The "Premium" certification is for features far beyond what a typical set top box utilize, such as 18gbps, 4K60HZ and BT.2020. I don't feel that would even be a problem, especially since I moved that cable to link my Oppo 4K player and I get full picture, audio, DV, etc … which leads me to believe the cable is NOT the issue.


The part of the recycled box I can totally agree with. I will get them one more shot today. Still strange that it works perfectly with any cable on the front AUX HDMI port...
Have you tried setting the STB to a fixed 1080i resolution yet?

The front aux port has a more limited bandwidth than the rear ports and supports only YCbCr 4:2:2. Since this is reported to the player device by the receiver's EDID, the player is supposed to automatically adjust the signal that it generates. My current suspicion is that the STB is trying to generate an inappropriate video signal when it's connected to the higher-bandwidth rear HDMI ports.

ETA: HDMI audio is transmitted in the "vertical retrace interval" of the video signal, so a partially messed up video signal can mess up the audio.
 

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Discussion Starter · #7 ·
Update: went back and replaced the 201 with an Arris DCX3600-M. I understand this is an older box, but the audio is working perfectly with this one. Bonus: clock on the front;I really missed that.
 
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