Table of Contents
- Is your FRITZ!Box 5690 Pro or 7690 throttling fiber speeds since the latest firmware?
- Manufacturer Confirms Performance Bugs in Newest Firmware
- Which Models Are Affected?
- Identifying the Symptoms
- Symptom: A 1 Gbit connection slowing to a “snail’s pace” (e.g., dropping to 8–9 Mbps).
- The Technical Cause
- Immediate Workaround: Disable Packet Acceleration
- The Permanent Solution
Is your FRITZ!Box 5690 Pro or 7690 throttling fiber speeds since the latest firmware?
Manufacturer Confirms Performance Bugs in Newest Firmware
If your internet speed has dropped recently, the latest router software might be the cause. AVM, the manufacturer of FRITZ!Box, officially confirmed performance issues with the FRITZ!OS 8.20 update. While older models received stable versions of this firmware last year, the rollout for newer flagship models has introduced significant stability problems.
Which Models Are Affected?
The performance degradation specifically impacts users of high-end, newer hardware. Reports confirm severe throttling on these units:
- FRITZ!Box 5690 Pro
- FRITZ!Box 7690
- FRITZ!Box 5690 XGS
Users with older units like the 7590 generally remain unaffected, as they received stable updates months ago.
Identifying the Symptoms
The issue manifests clearly for users on fiber optic connections. You might notice your download and upload speeds deteriorating over time, rather than failing instantly.
Symptom: A 1 Gbit connection slowing to a “snail’s pace” (e.g., dropping to 8–9 Mbps).
Trigger: The slowdown often occurs when the router connects to an external fiber optic modem (ONT).
Consistency: A restart fixes the speed temporarily, but the throttling returns within a day.
The Technical Cause
The root of the problem lies in the “Packet Acceleration” feature. Technical analysis suggests that the firmware mishandles hardware acceleration when connected to external modems. This conflict forces the router to throttle data throughput significantly.
Immediate Workaround: Disable Packet Acceleration
You can restore your speed temporarily without waiting for a new update.
- Log in to your FRITZ!Box user interface.
- Navigate to Help and Info.
- Select FRITZ!Box Support.
- Find the Packet Acceleration setting.
- Disable this function.
Note: This is a temporary measure. Some users report that this setting may reset after a device restart, requiring you to repeat the process.
The Permanent Solution
AVM is actively working on a patch. Support teams have admitted to the bug, stating that “slight performance changes may occur in certain operating states”.
- Current Status: A beta version (FRITZ!OS 8.24) is currently in testing and appears to resolve the throttling issue.
- Timeline: If you are comfortable with beta software, you can update now; otherwise, the official stable release should follow shortly.