Just noticed my comment above is now confirmed in the Wiki by Frodo:
How can I sort the epg-channels ?
You can sort the channels in setuptv. Note that each tv-group can have a different sorting.
The default group seen in mediaportal is called 'All Channels'. So In TVServer Setup -> TV Channels.
You have on the right, Channnels, Analog Channel and All the Channels
(analog channels or other, depends your tv card)
Choose "all the Channels" and order it as you want.
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