Tvheadend

Hi,

I run tvheadend within XBMC 11.0 RC1 (?) and mostly it works fine.
But, my dvb-c adapters (Terratec Cinergy C HD) falls asleep if i dont keep tvheadend streaming the tvsignal.
When selecting channels i get 'No input detected'
It happens on both unencrypted and encrpyted channels.
To wake the cards i have to access tvheadends webgui and select 'Map dvb services to channels' and choose 'save'
After that the cards are awake and everythings fine.
How can i resolve this problem?
I'm wondering if i need to put in Technotrend 1501's instead, seems that these Terratec are a bit crappy.
In windows they worked every second boot :/ Even dvb-viewer couldn't use them sometimes.

Loglevel debug: enabled
Mar 04 10:18:41 htsp: Got connection from 127.0.0.1
Mar 04 10:18:41 htsp: 127.0.0.1: Welcomed client software: XBMC Media Center
Mar 04 10:18:41 htsp: 127.0.0.1 [ XBMC Media Center ]: Identified as user tvheadend
Mar 04 10:18:41 htsp: 127.0.0.1 [ tvheadend | XBMC Media Center ]: Privileges raised
Mar 04 10:18:45 htsp: Got connection from 127.0.0.1
Mar 04 10:18:45 htsp: 127.0.0.1: Welcomed client software: XBMC Media Center
Mar 04 10:18:45 htsp: 127.0.0.1 [ XBMC Media Center ]: Identified as user tvheadend
Mar 04 10:18:45 htsp: 127.0.0.1 [ tvheadend | XBMC Media Center ]: Privileges raised
Mar 04 10:18:45 cwc: DVB-C adapter1/Com Hem, Stockholm: 378,000 kHz/Disc. Channel using CWC 127.0.0.1:10000
Mar 04 10:18:45 subscription: "127.0.0.1 [ tvheadend | XBMC Media Center ]" subscribing on "Disc. Channel", weight: 150, adapter: "DVB-C adapter1", network: "Com Hem, Stockholm", mux: "Com Hem, Stockholm: 378,000 kHz", provider: "Com Hem", service: "Disc. Channel", quality: 100
Mar 04 10:18:56 Transport: DVB-C adapter1/Com Hem, Stockholm: 378,000 kHz/Disc. Channel: Status changed to [Graceperiod expired]
Mar 04 10:19:00 cwc: DVB-C adapter1/Com Hem, Stockholm: 378,000 kHz/Disc. Channel using CWC 127.0.0.1:10000
Mar 04 10:19:02 htsp: 127.0.0.1 [ tvheadend | XBMC Media Center ]: Disconnected
Mar 04 10:19:02 subscription: "127.0.0.1 [ tvheadend | XBMC Media Center ]" unsubscribing from "Disc. Channel"
Mar 04 10:19:03 htsp: 127.0.0.1 [ tvheadend | XBMC Media Center ]: Disconnected
Loglevel debug: disabled