I posted to this thread on 5/21/19. Since then my SC-1222-k receiver has been repaired under the program and returned to me (on 6/18/19). I hooked it back up yesterday, and everything is working as it should.
The repair description stated: "No audio. Replaced HDMI board and checked all ports and channels." The lone replacement part is shown as #AWX1200
(Digital Main ASSY). PanurgyOEM did a thorough cleaning of all the components as inside the case is perfectly clean.
Initially, Technical Support at Onkyo/Pioneer offered a trade-in for SC-LX701 in amount of $960. I inquired as to whether PanurgyOEM was still performing repairs. Their response was that the repair program had ended several months ago; however, they noted a board was available and offered me the repair option, which I took. I submitted a support request via Onkyo website on 4/22/19 and had the repaired received back in my hands on 6/18/19. Without this thread, I never would have known there was a repair program for this issue. For that, I say thank you to Edllguy and others who worked to bring this issue to the attention of the AVSforum members, and kept working with Onkyo/Pioneer.
I have not provided the below for the thread, but will do so now.
Please state the following:
Pioneer receiver model/number: SC-1222-K
Build date (MFD: month & year):
Purchase date: 6/30/13
UE22 Error display date: Week of 4/15/19
Receiver positioning/placement statement: media cabinet; 3 inches of space at each side and top, open at rear and front.
Indicate if your Pioneer receiver saw low, medium, or high usage in your set up: High Usage. Basically, 14 to 16 hours daily since purchase.
Description of your experience with the UE22 error and the events that led up to your Pioneer receiver eventually failing: UE22 code began flashing. Sound quality diminished, with noticeable crackling/noise from speakers. When receiver was turned off then on again, sound would cut out multiple times over 15 minutes, before finally stabilizing.