hdmi input

[shirtpants]

envy all-in-one 32-a0055 has bright dashes all over screen when I hook up dish joey.  Bluray and ps4 works fine with same cable

[Echo_Lake]

@shirtpants
Thank you for posting on the HP Support Community.

Don't worry as I'll be glad to help, as you've mentioned other devices are functioning fine with the HDMI cable this proves the functionality of HDMI port. As we have limited support boundaries in the support community as of now. 

I would request you to reach out to our HP Smart Friend Support and our Support Engineers should be able to sort this out. HP Smart Friend Support can be reached by clicking on the following link: www.hp.com/contacthp/

Please feel free to contact us here anytime you need any further assistance. Please click “Accept as Solution” if you feel my post solved your issue, it will help others find the solution.

[chortlemortal]

I think I am having a similar problem plugging in an Xfinity Flex running 4K (really UHD).  What I think is happening is there are two HDMI chips involved, the sender and the receiver, and they need to handshake - but what starts off the handshake?  If you switch to HDMI when the sender is up and running you get white noise on the screen.  However, if you switch to HDMI and then  immediately either plug in or power-up the sender, then you get the picture.  I suggest giving this a try.

Since this problem is so bothersome and my Xfinity Flex does not have a power switch (it expects to be running continuously) I have installed a wireless controlled power plug, so I can turn on and off the sender from my Iphone. 

What is irritating is that once it is working, if you switch back to PC video that works, but if you switch back to HDMI input again, you are back to the white noise.  So I have to toggle power on my sender again.  Really hard to tell if it is a sender problem or a receiver (HP) problem.  But is is a handshake and the HP should be monitoring the HDMI input (probably in firmware or an FPGA) to detect changes and restart the handshake.  

I hope my workaround works for you.  I think I have the same computer as you an "HP Envy All-in-One-A055" but it is not in the Pavilion family as afar as I can  tell.