How to Fix Slow WiFi on a Samsung QLED TV: DNS, 5GHz Band Selection, SmartThings Network Reset, and Tizen OS Update Fixes

Samsung QLED TVs — from the QN-series and Neo QLED line to The Frame — are among the most capable streaming televisions available, but Tizen OS’s default network settings are not always optimized for speed. If your Samsung QLED is buffering on Netflix, stuttering through YouTube 4K, or reporting a “weak network connection” warning despite a fast home network, the problem is almost always fixable without a service call.

This guide covers every practical fix in order of impact, starting with the changes most likely to deliver an immediate improvement.

1. Switch to the 5 GHz Band (Or Separate Your SSIDs)

Most Samsung QLED TVs released from 2019 onward support both 2.4 GHz and 5 GHz WiFi. The 2.4 GHz band offers wider range but tops out at around 150–300 Mbps in real-world conditions and is heavily congested in apartments and dense neighborhoods. If your TV defaulted to 2.4 GHz during initial setup, switching to 5 GHz alone can double or triple your actual streaming throughput.

Fix: Go to Settings → General → Network → Open Network Settings → Wireless. Disconnect from your current network and reconnect, this time selecting your router’s 5 GHz SSID (often labeled with “5G” or “_5GHz” at the end). If your router uses a single combined SSID for both bands (band steering), log into your router’s admin panel and create a separate 5 GHz SSID so you can connect the TV to it explicitly.

Is Your TV Close Enough to the Router for 5 GHz?

The 5 GHz band has shorter range than 2.4 GHz. If your TV is more than two rooms away from your router, 5 GHz signal may be too weak to sustain 4K streaming — which typically requires at least 25 Mbps sustained. In that case, a mesh WiFi satellite placed in the same room as the TV is a better fix than forcing a weak 5 GHz connection. See our guide to the best mesh WiFi systems for large homes for recommendations, or our WiFi signal strength dBm guide to understand what signal level you actually need.

2. Change Your DNS Servers to Google or Cloudflare

Tizen OS defaults to your ISP’s DNS servers, which are often slow and geographically distant from Samsung’s content delivery networks. Switching to Google Public DNS (8.8.8.8) or Cloudflare (1.1.1.1) reduces lookup time for every streaming domain your TV resolves — YouTube, Netflix, Disney+, Amazon Prime Video — and can visibly speed up app launch times and reduce time-to-first-frame on video. This is one of the highest-impact, lowest-effort fixes available.

How to Change DNS on a Samsung QLED TV

1. Go to Settings → General → Network → Network Status.
2. Tap IP Settings at the bottom of the status screen.
3. Under DNS Setting, change from Obtain Automatically to Enter Manually.
4. Type 8.8.8.8 (Google) or 1.1.1.1 (Cloudflare) as the primary DNS.
5. Save and run a network status check to confirm connectivity.

Google DNS (8.8.8.8 / 8.8.4.4) is the most widely tested choice for streaming. Cloudflare (1.1.1.1 / 1.0.0.1) is slightly faster in many regions and has a strong privacy record. Either option is a significant improvement over most ISP defaults. For background on how DNS affects your speeds, see our guide on how internet speed actually works.

3. Power-Cycle Your TV and Router Fully

A full power drain clears both the TV’s network stack and any stale DHCP leases on your router. This is different from pressing the remote standby button, which leaves the TV in a low-power state with its network adapter still active and potentially holding a degraded connection.

1. Press the TV remote power button, then unplug the TV power cable from the wall.
2. Unplug your router and modem from the wall.
3. Wait a full 60 seconds — do not rush this step.
4. Plug the modem in first, wait for all lights to stabilize (about 60 seconds), then plug in the router.
5. Finally, plug the TV back in and reconnect to WiFi.

A full power-cycle fixes a surprisingly large number of “mysteriously slow” streaming sessions, especially on TVs that have been in standby for days without a complete restart.

4. Clear App Cache in Tizen OS

Tizen OS does not automatically purge app caches. Over time, YouTube, Netflix, Samsung TV Plus, and other apps accumulate hundreds of megabytes of cached data that consume RAM and can cause buffering and sluggish UI response — even when your network is fast.

To clear cache for a specific app on a Samsung QLED TV (Tizen 6.5 and later, which covers 2022-model and newer):

1. Go to Settings → Apps.
2. Select the app you want to clear (e.g., YouTube or Netflix).
3. Tap Storage → Clear Cache.
4. Relaunch the app and test streaming performance.

On older Tizen versions, the per-app cache path may not be available. In that case, a Smart Hub reset clears all app data at once: Settings → Support → Self Diagnosis → Reset Smart Hub. Note that this signs you out of every streaming service, so have your credentials ready before proceeding.

5. Update Tizen OS Firmware

Samsung has released multiple Tizen OS updates since 2023 that specifically address WiFi stability and streaming performance. TVs running outdated firmware can exhibit slow DHCP renewal, poor 5 GHz band adhesion, and buffering regressions that are resolved in later releases. Samsung’s 2024 QLED lineup received Tizen 9.0 in mid-2025, with notable network stack improvements over Tizen 8.

How to update: Settings → Support → Software Update → Update Now. The TV needs an active internet connection to check for updates. If the TV cannot download the update due to poor WiFi, you can update via USB by downloading the correct firmware file from Samsung’s support site onto a FAT32-formatted USB drive and inserting it into the TV’s USB port.

6. Use SmartThings for Remote Network Diagnostics

If your Samsung TV is registered in the SmartThings app, you can run a remote network check and even push new WiFi credentials to the TV without touching the remote — useful if you recently changed your router password or SSID.

1. Open SmartThings on your phone and tap Devices.
2. Select your Samsung TV from the device list.
3. Tap the three-dot menu → Settings → WiFi.
4. SmartThings displays the current band, signal strength, and connection status, and lets you trigger a network reconnect or change networks remotely.

SmartThings also surfaces error codes and connection logs that the TV’s own settings menu doesn’t expose, making it a valuable first step in diagnosing whether the problem is signal strength, authentication, or DNS.

7. Reset Network Settings (Last Resort Before Factory Reset)

If every fix above has been tried and the TV still reports slow speeds or intermittent disconnects, a network settings reset gives Tizen OS a completely clean network state. It clears all saved WiFi credentials, DNS overrides, and IP configurations.

Path: Settings → General → Network → Reset Network. Confirm on the dialog that appears. After the reset, go back to Open Network Settings and reconnect from scratch — remembering to select the 5 GHz SSID and manually re-enter your DNS servers (8.8.8.8) as described in Fix 2.

Quick Checklist

1. Connect to 5 GHz band — Settings → General → Network → Open Network Settings, pick your router’s 5G SSID.
2. Change DNS to 8.8.8.8 — Settings → General → Network → Network Status → IP Settings → DNS Setting → Enter Manually.
3. Full power-cycle: unplug TV, router, and modem for 60 seconds.
4. Clear cache for slow streaming apps via Settings → Apps.
5. Update Tizen OS firmware via Settings → Support → Software Update.
6. Use SmartThings to diagnose signal strength and push credentials remotely.
7. Reset network settings if all else fails, then reconnect to 5 GHz with manual DNS.

Fixes 1 and 2 alone resolve the majority of Samsung QLED slow WiFi complaints. If your TV is still struggling after all seven steps, run a speed test from a laptop in the same room as the TV to confirm your broadband plan is delivering the speeds you expect. If the laptop gets full speed but the TV does not, your TV’s WiFi adapter may be the bottleneck — in which case a direct Ethernet connection via a USB-C-to-Ethernet adapter (on supported models) or a dedicated WiFi–to–Ethernet bridge is the most reliable long-term fix.