Delay using 30-sec skip on recordings

Channels DVR Server
#1

I don't record too many shows, but occasionally I record a game so I'm not sure how long this may have been an issue. But recently I've noticed that the 30-sec skip doesn't work very smoothly on recordings. Usually the first couple of skips are lightning fast, but then it can really slow down and take 5+ seconds for the show to continue after I press the skip button once. This doesn't happen when using the live TV buffer, only when playing back recordings. This seems to happen on all clients, including the web player.

My server is a 2014 iMac with an external SSD (brand new because I wondered of the older external SSD was the cause). I mostly watch on my ATV4K 2021, but it also happens on my ATV4K, iPhone, iPad and web player.

When I run a speed test on the DVR server from my iPhone, I get ~600mbit/s download, <3ms latency, ~1.5ms jitter. I don't see anything in the log that appears helpful.

Any suggestions?

#2

I believe the buffer on the client stretches to about 70 seconds when watching a recording, at least on my Apple TV. You can see the buffer length in real time if you view stats. In practice this means you can skip ahead 30 seconds twice really quickly. After that the buffer will be almost depleted so further skips will be slower. At that point how long it takes is highly dependent on the speed of your network connection and server. If your clients are wifi they will definitely be slower than ones that are wired gigabit.

#3

I am not using wifi, but I don't notice any delay whatsoever on a completed recording. I can skip 30 seconds instantly again and again through the entire program. Auto commercial skip seems instant too.

I have seen delays before when watching a recording that is still in progress however. I think it could be too many IO tasks on the same file for the drive which causes it to slow down. If watching a recording that is still in progress, I tend to skip by pausing and scrolling, rather than tapping 30-sec skip constantly.

#4

If you are on the AppleTV TestFight beta there’s a setting under the Debug menu called Always use HLS Streaming.

If you would be willing to test this out and see if your experience is better, please make sure you’re on a recent DVR pre-release build and try enabling that setting and see if seeking is any faster.

Note: It will make tuning to Live TV channels slower, so you won’t want to leave it on permanently, but it’ll be a useful test.

#5

I just recently bought an ATSC 3.0 tuner (HDHR Flex 4k) and have noticed that fast-forwarding works better on 3.0 recordings for some reason. The audio might come back slightly after the video starts, but the video seems to start faster once you've overrun the buffer. Tivo 4k (Google TV).

Unfortunately the HDHR only has two 3.0 tuners, but that probably won't matter because the programming I FF through the most is the news. For other I have commercial skip which doesn't seem to be affected by delay.