They have had this kind of problem for a long time now. I have both recast and the stick wired to the same switch (and have tried several switches..). Picture always looks great 100% of the time watching live TV. When I watch a recording though, if I watch it undisturbed for 15+ minutes, the picture starts degrading and only gets worst. Strangely enough, it's instantly fixed by just rewinding 10s or forwarding 30s. At least for another 15+ minutes. Most of the time though this goes entirely unnoticed because a commercial will come on and I forward it anyway.
I record a lot of PBS shows and also record a lot of sports. There are very little commercial breaks if any to fast forward to. I'm really surprised Amazon hasn't found a fix yet. The Recast almost becomes useless because the playback from the DVR is terrible.
I had excellent OTA reception with no buffering issues until this past week. All of a sudden and for no apparent reason, buffering became so bad that OTA channels were unwatchable. I tried most of the remedies posted above, but nothing worked. I spoke to Amazon technical support and was advised to switch the Recast connection from Ethernet to WiFi to be "on the same network" as our WiFi-connected Fire TV Sticks. I was very skeptical because everything is essentially on the same network, but I agreed to give it a try. That completely resolved all of the buffering problems. This may make more sense to someone with more networking/multicast knowledge, but I am just happy to have fixed the problem.
I have a theory that this is due to disk fragmentation or the overhead of background disk space reclamation once the disk gets full. I noticed buffering start once I started getting the disk full messages indicating that it would start deleting unprotected shows. I did an experiment and went through and deleted most of my old unwanted recordings and have seen the buffering disappear for the time being. I would be interested in others trying this experiment. My feeling is that the background storage cleanup is running while I am trying to play my recordings or that the cleanup is just not freeing enough space to prevent disk fragmentation slowing access during playback.
If your manual disk cleanup fixes buffering for you then I suspect this is the problem.
Since restarting the Fire TV Recast and Fire TV Stick did not fix my constant buffering issue, a helpful Amazon Fire TV Recast rep suggested the following, which solved the problem:
1) Unpair the Recast - On Fire TV menu navigate to Settings > Live TV > Live TV Sources > Fire TV Recast > Unpair this Fire TV 2) Hard reboot the Recast - After the Recast is Unpaired, unplug the Recast for a minute. Plug back in. 3) Reboot the Fire TV -On Fire TV menu navigate to Settings > My Fire TV > Restart -(Note that my Fire TV Stick froze during this process so I actually ended up unplugging the Fire TV Stick for a minute.) 4) Pair the Recast - After the Fire TV Stick has rebooted and is back up and running (this took a few minutes): - On Fire TV menu navigate to Settings > Live TV > Live TV Sources > Fire TV Recast > Pair a Fire TV Recast 5) Channel Scan - After the Recast is Paired: - On Fire TV menu navigate to Settings > Live TV > Live TV Sources > Fire TV Recast > Channel Scan
Once the channel scan was over I was back in business. All my previous favorites were saved.
My experience is the buffering comes back. Depends on throughput. You can check the throughput in the diagnose screen:
1. press rewind + left direction at the same time for 3 seconds, then release and press the menu button
2. scroll to the bottom and select more.
The throughput value is all over the place. One time reads 45 +/- 38 Mbps, then is 12 +/-10 Mbps, then 55+/-47 Mbps, My firetv recast is wired and the fire tv 4k stick is wireless to a dedicated router. Nothing else is connected to the router. I thinkg the buffering happens when the throughput drops.