I tried a 10db attenuator with no results. I am considering getting an FM Trap (Mention in one of the links posted by Roginator) https://www.tvtechnology.com/opinions/dtv-interference-on-vhf-channels-413 after that, I guess I am out of options. I direct messaged the Fire TV twitter account, to see if I can reach someone who could contact their dev team, but got no reply. Really disappointing.
I have been having this same problem with FYI 20.1 in Indianapolis. When switching to 20.1 the signal is perfect for the first ten to twenty seconds and then pixilation and screen freezes start. Bypassing the Recast I have no issues. I am 5 miles away from the Antenna farms on the Northwest side of Indy. I have a Channel Master Metrotenna40 on my roof top (approximately 30 feet off the ground) pointed West, Northwest. I have about a 60 foot run of coax from the antenna to the recast. Since installing the recast and being presented with this issue I have moved the antenna from 10 feet off the ground located on the Southwest corner of the house to the roof on the Northwest corner of the house, added, at the recommendation of several people (one being an Engineer at our local FOX affiliate), a LTE filter, 6db Attenuator (to address a possible over powered signal) a high pass filter (remove FM interference), a Channel Master distribution amplifier since I split the antenna between multiple TVs (with terminators on the unused out ports), and an Channel Master adjustable gain pre-amplifier utilizing loan gain (suggested to address signal degradation between the antenna and the distribution amplifier since there is 50 feet of coax between the two). Nothing has helped and the issue persists ONLY for 20.1 while every other Indy channel comes in perfect clear all the time. I previously had a HD Home Run Quatro with the same issue (only FYI 20.1) that Silicon Dust was never able to resolve. That is why I bought the Recast.
Interesting. I looked up WFYI on Rabbitears.info and found it has 225 kW power. I thought, "wow! that's powerful!" until I looked at the stations around me. The most powerful, by far, is also the closest (3 miles) KTBY at 234 kW. The others are a fraction of that.
That being said, I don't have to aim my 2nd floor antenna at THAT station to receive it just fine. Maybe if you aimed your antenna north instead of northwest? Just something to try.
I have tried a few things to try to troubleshoot the pixelation issue. First was to move my outdoor antenna to a new location and replace the pre amp with a Channel Master CM-7778hd Amplify +running at low power setting. Pre amp has FM and LTE filters built in my old LNA-200 only had FM blocking but I don't believe noise was the issue. This Helped all of my channels signal strength most are 30db + or - about 3 db. I am still having issues although not quite as bad. My HTPC records from the same antenna and can produce a perfect recording of the same channel while Recast breaks up. At this point I think it is either the video codecs in use or maybe poor performance with multipath, although right now the wind is blowing hard and 13 came in fine during a quick check so multipath may not be it.. Not sure what to try next.
I can't figure it out either. Here lately WJZ-13 has been coming in pretty good. It seems like it has good days and bad. I installed -21dB of attenuators and the LTE filter. I use the HDhomeRun to check the signal strength and brought the signal down to 80%. Reconnected the Recast and WJZ seems ok but time will tell. Will keep you posted.
I was able to get an e-mail to WFYI 20's Director of Engineering Operations today. I explained the situation and his response was "The only significant difference with our signal and the others you mention is that we transmit two 1080i HD channels (20.1 and 20.2) along with one SD channel while the others only transmit one HD Channel. I don't expect this is a problem but you might check with the manufacturer as to whether the Recast has been known to have any problem with decoding two HD channels on a single broad cast signal." I wonder if the other stations where this problem is being experienced are doing the same thing? I wonder how you get an inquiry to someone at Amazon? Seems there is no customer support only these forums.