This posting is older than 6 months and can contain outdated information.
The detail about custom keyboard shortcut is very important as, if you
didn't reset it back to what factory defaults are, it will not work
with Remote Buddy. Remote Buddy's support for SlingPlayer relies on
correct keyboard shortcuts.
Also, are you using Remote Buddy 1.1? Older releases will not load the
latest version of the SlingPlayer Behaviour update.
What happens, if you press the P and U keys (just the keys, without
any modifiers) in SlingPlayer?
Which localization and keyboard layout are you using?
Best regards,
Felix