Activity stream doesn't update

Hi,
when I post a news update in the “what’s news” box, the text message doesn’t appear. I need to refresh the page myself and it appears.
I tried to install the plugin “RS Buddypress Activity Refresh” but nothing change.

I tried to desactivate my others plugins but its always the same.

thanks

Thibaut
My plugins details :

— WordPress Configuration

Version: 3.8.1
Permalink Structure: /%postname%/
Active Theme: Kleo 1.0
Show On Front: page
Page On Front: Accueil (#10)
Page For Posts: Unset
Remote Post: wp_remote_post() works
Table Prefix: Length: 17 Status: ERROR: Too long
WP_DEBUG: Disabled
Memory Limit: 40M

— WordPress Active Plugins

Akismet: 2.5.9
BP Activity Autoloader: 1.0
Bp Chat: 1.1 trunk
BP Disable Activation Reloaded: 1.0
BP Groups Suggest Widget: 1.0.3
BP Profile Search: 3.5.6
BuddyMenu: 2.2.0
BuddyPlug: 0.3
BuddyPress: 1.9.2
BuddyPress Activity Privacy: 1.3
Buddypress Sitewide activity widget: 1.1.7
Buddypress Xprofile Custom Fields Type: 1.5.8.5
Invite Anyone: 1.1.0
K Elements: 1.0.0
OptimizeMember: 1.0.8
OptimizePress: 2.1.8.1
Revolution Slider: 4.1.4
RS Buddypress Activity Refresh: 1.8
rtMedia for WordPress, BuddyPress and bbPress: 3.6.7
UpdraftPlus – Backup/Restore: 1.8.12
User Name Availability Checker for wordpress/buddypress: 1.0.4
WordPress Social Login: 2.1.6
WP-Memory-Usage: 1.2.2
WPBakery Visual Composer: 3.7.4
WP Social Invitations: 1.4.4.4

— WordPress Inactive Plugins

BuddyPress Block Activity Stream Types: 0.5.2
BuddyPress Extended Friendship Request: 1.0.2
Nextend Facebook Connect: 1.4.59
Paid Memberships Pro: 1.7.7
Social Login for wordpress: 5.5
Welcome Pack: 3.3

— Webserver Configuration

PHP Version: 5.4.25
MySQL Version: 5.1.73-log
Webserver Info: Apache

— PHP Configuration

Safe Mode: No
Memory Limit: 256M
Upload Max Size: 40M
Post Max Size: 8M
Upload Max Filesize: 40M
Time Limit: 50000
Max Input Vars: 5000
Display Errors: On (1)

— PHP Extensions

cURL: Supported
fsockopen: Supported
SOAP Client: Installed
Suhosin: Not Installed

— Session Configuration

Session: Enabled
Session Name: PHPSESSID
Cookie Path: /
Save Path: /tmp
Use Cookies: On
Use Only Cookies: On

### End System Info ###