Who did you order the cable from, as their warranty is vendor dependent?
One other question. What are you powering that cable from, a voltage inserter, or or do you have an HDMI version 2.1a? If you are not powering it from either of those two methods, then more likely your HDMI port is failing and actually it could even take down your HDMI board.
I should have said HDMI 2.1a and HDMI 2.3 version. Depending on the date of your unit the HDMI version will be either 2.1 or 2.3. Only the HDMI 2.3 version can power a Ruipro cable or any active cable without serious damage to the HDMI board occuring.
This is a confusing issue, and causes a lot of damage to HDMI boards.
Active cables like Ruipro draw 300 ma to power the converters.
Only HDMI versions 2.1a and 2.3 provide 300 ma, all other versions only provide 50 ma. So unless you use a voltage inserter with all ports other than 2.1a or 2.3 serious damage will occur to the HDMI board over time or even right away.
Which version your AVM 70 has depends on its age, but should be marked on the port your Ruipro cable is connected to. Earlier versions of the AVM 70 had 2.1 ports and CAN NOT safely power cables like Ruipro. Later versions have HDMI 2.3 and can safely power your Ruipro cable.
So when I was using my Marantz 7705 and then the 7706 I used a voltage inserter. My Marantz AV 10 has HDMI 2.3 and I have dispensed with the voltage inserter.
I installed a Ruipro active cable the same length as yours in 2019, and it is still working fine with zero issues.
So the bottom line is, if your AVM 70 has HDMI 2.1 then you have almost certainly have an issue with your HDMI board and not the cable.
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