Repository: yt-dlp
Issue: Unable to stream from IBM Ustream:channel
Labels: site-bug,triage

### DO NOT REMOVE OR SKIP THE ISSUE TEMPLATE

- [X] I understand that I will be **blocked** if I *intentionally* remove or skip any mandatory\* field

### Checklist

- [X] I'm reporting that a **supported** site is broken
- [X] I've verified that I'm running yt-dlp version **2023.03.04** ([update instructions](https://github.com/yt-dlp/yt-dlp#update)) or later (specify commit)
- [X] I've checked that all provided URLs are playable in a browser with the same IP and same login details
- [X] I've checked that all URLs and arguments with special characters are [properly quoted or escaped](https://github.com/yt-dlp/yt-dlp/wiki/FAQ#video-url-contains-an-ampersand--and-im-getting-some-strange-output-1-2839-or-v-is-not-recognized-as-an-internal-or-external-command)
- [X] I've searched [known issues](https://github.com/yt-dlp/yt-dlp/issues/3766) and the [bugtracker](https://github.com/yt-dlp/yt-dlp/issues?q=) for similar issues **including closed ones**. DO NOT post duplicates
- [X] I've read the [guidelines for opening an issue](https://github.com/yt-dlp/yt-dlp/blob/master/CONTRIBUTING.md#opening-an-issue)
- [X] I've read about [sharing account credentials](https://github.com/yt-dlp/yt-dlp/blob/master/CONTRIBUTING.md#are-you-willing-to-share-account-details-if-needed) and I'm willing to share it if required

### Region

Australia

### Provide a description that is worded well enough to be understood

I am not sure if this is related to [#3702](https://github.com/yt-dlp/yt-dlp/issues/3702) as this is for channel.
I've noticed that ustream today has suddenly gotten quick snarky about playing m3u8's from their iPhone URL - so I am not sure if they have made changes holistically to prevent side access.

### Provide verbose output that clearly demonstrates the problem

- [X] Run **your** yt-dlp command with **-vU** flag added (`yt-dlp -vU <your command line>`)
- [ ] If using API, add `'verbose': True` to `YoutubeDL` params instead
- [X] Copy the WHOLE output (starting with `[debug] Command-line config`) and insert it below

### Complete Verbose Output

```shell
[debug] Command-line config: ['-vU', 'https://video.ibm.com/channel/iss-hdev-payload']
[debug] Encodings: locale utf-8, fs utf-8, pref utf-8, out utf-8, error utf-8, screen utf-8
[debug] yt-dlp version stable@2023.03.04 [392389b7d] (pip)
[debug] Python 3.11.2 (CPython x86_64 64bit) - macOS-13.2.1-x86_64-i386-64bit (OpenSSL 1.1.1t  7 Feb 2023)
[debug] exe versions: ffmpeg 5.1.2 (setts), ffprobe 5.1.2
[debug] Optional libraries: Cryptodome-3.17, brotli-1.0.9, certifi-2022.12.07, mutagen-1.46.0, sqlite3-2.6.0, websockets-10.4
[debug] Proxy map: {}
[debug] Loaded 1786 extractors
[debug] Fetching release info: https://api.github.com/repos/yt-dlp/yt-dlp/releases/latest
Available version: stable@2023.03.04, Current version: stable@2023.03.04
yt-dlp is up to date (stable@2023.03.04)
[generic] Extracting URL: https://video.ibm.com/channel/iss-hdev-payload
[generic] iss-hdev-payload: Downloading webpage
WARNING: [generic] Falling back on generic information extractor
[generic] iss-hdev-payload: Extracting information
[debug] Looking for embeds
[debug] Identified a twitter:player iframe
[ustream] Extracting URL: https://ustream.tv/embed/17074538
[ustream] 17074538: Downloading webpage
ERROR: [ustream] 17074538: Unable to extract content video IDs; please report this issue on  https://github.com/yt-dlp/yt-dlp/issues?q= , filling out the appropriate issue template. Confirm you are on the latest version using  yt-dlp -U
  File "/usr/local/Cellar/yt-dlp/2023.3.4/libexec/lib/python3.11/site-packages/yt_dlp/extractor/common.py", line 694, in extract
    ie_result = self._real_extract(url)
                ^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/Cellar/yt-dlp/2023.3.4/libexec/lib/python3.11/site-packages/yt_dlp/extractor/ustream.py", line 172, in _real_extract
    content_video_ids = self._parse_json(self._search_regex(
                                         ^^^^^^^^^^^^^^^^^^^
  File "/usr/local/Cellar/yt-dlp/2023.3.4/libexec/lib/python3.11/site-packages/yt_dlp/extractor/common.py", line 1242, in _search_regex
    raise RegexNotFoundError('Unable to extract %s' % _name)
```