API: Seek not always jumping specified amount

Using the iOS Shortcuts app I have created a Shortcut to jump Channels on my Apple TV by 4 minutes (e.g. to skip an ad break when behind in the timeline).

I am using the following URL as per the API docs, calling it via "Get Contents of URL (POST)":

http://192.168.X.X:57000/api/seek/240

Most of the time this works as expected, jumping the full 240 seconds (4 minutes).

However, for no apparent reason, sometimes it jumps a much shorter length of time, not sure how long but guessing about 30 seconds. Despite being more than 4 minutes behind in the timeline. So I end up having to then manually skip through the rest of the ad break.

Any idea why this is happening?

Could be that the packets/piece of the recording that corresponds to where you want to skip to is missing some data.

When skipping forward and backward by set time increments, the video decoder can only really guess exactly where that is, and sometimes it doesn't quite work.