update docs (#536)

Signed-off-by: hsliu <liuhongsheng4@huawei.com>

docs/user_guide/examples/offline_inference/qwen2_5_omni.md

@@ -70,13 +70,6 @@ If media file paths are not provided, the script will use default assets. Suppor
 - `use_audio_in_video`: Extract audio from video
 - `text`: Text-only query
 
-### FAQ
-
-If you encounter error about backend of librosa, try to install ffmpeg with command below.
-```
-sudo apt update
-sudo apt install ffmpeg
-```
 
 ## Example materials
 

docs/user_guide/examples/offline_inference/qwen3_omni.md

@@ -57,13 +57,6 @@ If media file paths are not provided, the script will use default assets. Suppor
 - `use_audio`: Audio input
 - `text`: Text-only query
 
-### FAQ
-
-If you encounter error about backend of librosa, try to install ffmpeg with command below.
-```
-sudo apt update
-sudo apt install ffmpeg
-```
 
 ## Example materials