User agent spoofing

I’m having trouble with my IPTV provider.
He recently started blocking requests coming from Kodi.

I managed to retrieve the channel list by appending a custom user agent to the playlist URL:

Code:
Playlist-URL|User-Agent=Mozilla/5.0

However, this leaves me with a list of channels which I’m unable to play, because the provider also blocks Kodi on every stream request.

Again, I managed to view the channels by editing the playlist, and appending a custom user agent to every URL in it:

Code:
First-Stream-URL|User-Agent=Mozilla/5.0
Second-Stream-URL|User-Agent=Mozilla/5.0
...
Last-Stream-URL|User-Agent=Mozilla/5.0

It seems I’m not the only one with this kind of issue, so it would be cool to have a way to spoof the user agent for every request (playlist AND streams) without manual editing the playlist file.
Is it possible?