To connect Castr to Facebook Live with a custom RTMP destination, copy Facebook Live Producer’s Server URL and Stream Key, add Facebook Live in Castr using Setup with Server/Key, and paste each value into its matching field. Start the stream from Castr, then click Go Live manually in Facebook Live Producer.
Before you start: distinguish the two sets of RTMP details
Facebook’s Server URL and Stream Key are destination credentials: they tell Castr where to send the broadcast on Facebook. Castr has separate source-ingest credentials—its own RTMP URL and stream key—which an encoder uses to send video into Castr. Do not paste Facebook’s destination details into an encoder configured to send to Castr.
You will need access to the Castr livestream and the intended Facebook account, Page, or other destination supported in your account. Castr says the number of destinations available depends on the subscription plan. Check the current plan and destination options in your Castr account because plan terms can change. Castr’s livestream setup guide describes adding destinations.
Connect Facebook Live to Castr with Server/Key
- Open a Castr livestream. Sign in to Castr and open an existing livestream project or create one. In its dashboard, select Add destination or the platform-add control.
- Select Facebook Live and the server/key route. Choose Facebook Live, then choose Setup with Server/Key. Castr also offers a Facebook account-linking route, but it is a separate setup flow.
- Get Facebook’s destination details. Open Facebook Live Producer and, in the setup panel, select Use Stream Key. Copy the displayed Server URL and Stream Key. Facebook may offer a persistent stream key; Castr’s instructions describe enabling that option if you want to reuse the key. Treat it as a password: do not share or publish it.
- Enter the values in Castr. Return to the Facebook destination form in Castr. Paste Facebook’s Server URL into Castr’s Streaming Server field and Facebook’s Stream Key into Streaming Key. Add the stream title and description, select or add the stream source, and save or add the destination. See Castr’s server-and-key instructions for its field mapping.
- Start the stream from Castr. Start sending your video to Castr from the stream dashboard or connected source.
- Start the Facebook broadcast. Return to Facebook Live Producer and click Go Live after Castr starts sending the stream. With the server/key method, Castr says this Facebook step is manual; starting in Castr alone does not complete the broadcast.
- Verify the destination. Confirm Facebook shows the broadcast live and that the intended profile or Page is selected before sharing it with viewers.
Facebook and Castr can change interface labels or their placement. The labels above describe Castr’s documented workflow; if a control has moved, look for the equivalent stream-key setup or destination action in the current interface.
#1 Best Overall
- Read Before You Buy — No Video Output: These adapters support charging and USB 2.0 data transfer, but cannot transmit video signals. Except for standard USB webcams (which use USB data only), they are not compatible with HDMI/DisplayPort cables, video-capable USB-C hubs, or docking stations with video output.
- Convert USB-A Ports to USB-C: Designed to connect USB-C earphones, cables, flash drives, card readers, and other USB-C accessories to standard USB-A ports. Plug-and-play with no drivers or software required.
- Aluminum Alloy Housing: Built with a sturdy aluminum alloy shell that aids in heat dissipation and protects against daily wear and scratches. Designed to maintain a stable and secure connection.
- Compact & Travel-Friendly: The ultra-compact design allows the adapter to stay plugged into your device without blocking adjacent ports or adding bulk, reducing wear and tear on your original USB ports.
- 12-Month Warranty: Backed by a 12-month manufacturer warranty for peace of mind. Designed to meet strict quality control standards for reliable everyday performance.
Server/key or Facebook account linking?
| Route | What you do | What to check |
|---|---|---|
| Server/key (custom RTMP destination) | Copy Facebook’s Server URL and Stream Key from Live Producer and enter them in Castr. | After Castr starts sending, manually click Go Live in Facebook Live Producer. |
| Facebook API/account linking | Choose Continue with Facebook in Castr and authorize the account. | Confirm the current plan and that the account and intended destination type are available in your Castr account. Castr’s older guide describes user timelines, Pages, and groups, but current support should be checked in the account UI. |
Castr’s 2024 Facebook API guide says API integration was available on Multistream Plus and above and that Pages required a paid Castr plan. Those are dated plan statements, not a guarantee of current eligibility. Check Castr’s current offer before choosing that route. Castr’s Facebook API guide also reports historical Facebook eligibility and stream-duration rules; do not treat its 2024 figures as verified current Facebook requirements.
Troubleshooting
No video reaches Castr
Check the source encoder’s destination. If it is meant to send video into Castr, it must use Castr’s source-ingest URL and key from the Stream Source Setup panel—not Facebook’s Server URL and Stream Key. Castr’s source details guide explains where to find its ingest information.
Rank #2
- 5-in-1 USB-C Hub: Experience comprehensive connectivity featuring a Power Delivery input, two USB-A 2.0 ports, a USB-A 3.0 port, and an HDMI port. (Note: The USB-C power delivery input port is only for connecting an external wall charger to power your laptop and cannot power peripheral devices.)
- 90W Pass-Through Charging: Achieve optimal charging with 90W pass-through power to your laptop, supported by a total input of 100W, with the hub reserving 10W for operational efficiency. (Note: Wall charger not included.)
- Quick Data Transfers: Accelerate your productivity with rapid data transfers using a high-speed 5Gbps USB 3.0 port and two 480Mbps USB 2.0 ports.
- 4K HDMI Display: Enhance your visual experience with a hub capable of delivering 4K resolution at 30Hz in both mirror and extend modes. Please note that this hub is compatible with MacBook (macOS 12 and newer), Windows 10 and 11, ChromeOS, and laptops equipped with DP Alt Mode and Power Delivery. Note: This device is not compatible with Linux.
- What You Get: Anker USB-C Hub (5-in-1, 4K HDMI), welcome guide, 18-month warranty, and our friendly customer service.
Castr is sending, but Facebook is not live
For the server/key route, open Facebook Live Producer and select Go Live after Castr starts the stream. Also make sure you are viewing the intended Facebook destination.
Facebook does not connect to the Castr destination
Check that the Server URL and Stream Key were copied from Facebook Live Producer and pasted into the corresponding Castr fields. If you have replaced or changed a key, update the Castr destination to match.
Do these 3 things before closing this tab:
1Clear out junk files and repair common Windows errors2Scan for outdated or missing drivers - takes under a minute3Repair Windows errors before they cause bigger problemsRank #3
- Sleek 7-in-1 USB-C Hub: Features an HDMI port, two USB-A 3.0 ports, and a USB-C data port, each providing 5Gbps transfer speeds. It also includes a USB-C PD input port for charging up to 100W and dual SD and TF card slots, all in a compact design.
- Flawless 4K@60Hz Video with HDMI: Delivers exceptional clarity and smoothness with its 4K@60Hz HDMI port, making it ideal for high-definition presentations and entertainment. (Note: Only the HDMI port supports video projection; the USB-C port is for data transfer only.)
- Double Up on Efficiency: The two USB-A 3.0 ports and a USB-C port support a fast 5Gbps data rate, significantly boosting your transfer speeds and improving productivity.
- Fast and Reliable 85W Charging: Offers high-capacity, speedy charging for laptops up to 85W, so you spend less time tethered to an outlet and more time being productive.
- What You Get: Anker USB-C Hub (7-in-1), welcome guide, 18-month warranty, and our friendly customer service.
The encoder asks for a Castr username and password
Castr’s July 2026 source-ingest guide says username and password are not required for that encoder-to-Castr workflow; leave those fields empty. This applies to Castr ingest, not to Facebook destination credentials.
A persistent key was exposed
Keep a persistent stream key private because it can be reused. If it is exposed, replace or rotate it through Facebook’s available controls and update the corresponding key in Castr before streaming again.
Rank #4
- Dual Converters, Infinite Potential：Includes 2× USB C male to USB A female adapters and 2× USB A male to USB C female adapters. Perfect for a wide range of uses—tablets with Bluetooth keyboards, expand USB ports on macbook, and more. Two different converters for all your daily needs
- Next-Level 10Gbps & 3A Charging: No more slow 480Mbps, this usb to usb c adapter has a transfer speed of up to 10Gbps, allowing you to do more transferring in less time. This usb adapter fits both USB A and USB C charger, supporting up to 3A fast charging
- Upgraded Exquisite Craftsmanship: With an aluminum alloy housing and metal connector, the usbc to usb adapter is extremely durable and sturdy. Rigorously tested to withstand more than 10,000 times of plugging and unplugging, ensuring long-lasting performance
- Broad Compatible: The usb c to usb adapter widely supports all USB C/ USB A devices like laptops, tablets, cellphones, car chargers, and phone chargers. Such as compatible with MacBook Pro/Air 2023/2022, Thunderbolt 4/3 Devices,Apple MagSafe Watch 9/8/7/SE/Ultra, iPad Pro 2022/2021, Samsung Galaxy S23/S20/S10, and iPhone 17/16/15 Pro. Plug and play
- Please Note: To reach 10Gbps speed, keep the cable under 3.3 ft. For USB A Male to USB C adapters, try flipping the USB C connector. USB C Male to USB A adapters support bidirectional 10Gbps transfer within 3.3 ft
The destination or API option is unavailable
Review the destinations and limits shown for your current Castr subscription. Destination counts depend on plan, and the specific API eligibility described in Castr’s 2024 article may have changed.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Or let it run in the cloud
If your goal is a continuous YouTube stream of uploaded video rather than a Facebook broadcast, StreamNeo is a different workflow: upload a recording or build a playlist, add your YouTube stream key once, and go live. It loops the uploaded video from the cloud, so nothing has to stay on at home. Each slot streams the file as uploaded at any quality up to 4K 60fps for one flat price, and StreamNeo automatically recovers if YouTube drops the stream. The first day is free with no card required. Monthly pricing is $9.99 per month. StreamNeo is for YouTube only, not Facebook Live. Start your free StreamNeo day.
Free tools Windows power users keep installed
One-click scans. No signup required.
Quick Recap
Best Value
- 5-in-1 Connectivity: Equipped with a 4K HDMI port, a 5 Gbps USB-C data port, two 5 Gbps USB-A ports, and a USB C 100W PD-IN port. Note: The USB C 100W PD-IN port supports only charging and does not support data transfer devices such as headphones or speakers.
- Powerful Pass-Through Charging: Supports up to 85W pass-through charging so you can power up your laptop while you use the hub. Note: Pass-through charging requires a charger (not included). Note: To achieve full power for iPad, we recommend using a 45W wall charger.
- Transfer Files in Seconds: Move files to and from your laptop at speeds of up to 5 Gbps via the USB-C and USB-A data ports. Note: The USB C 5Gbps Data port does not support video output.
- HD Display: Connect to the HDMI port to stream or mirror content to an external monitor in resolutions of up to 4K@30Hz. Note: The USB-C ports do not support video output.
- What You Get: Anker 332 USB-C Hub (5-in-1), welcome guide, our worry-free 18-month warranty, and friendly customer service.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
