Tvheadend

Bit of a cryptic subject, apologies!

My setup: 2xDVB-S2, 1xDVB-T
Primary DVB-S2 card setup with Extra Priority 0
Secondary DVB-S2 with Extra Priority 10
DVB-T card setup with Extra Priority 30
Channels merged (So Channel 4 and Channel 4 HD are merged). Channels on all 3 adapters set to the same name, so all 3 adapters should be usable.
However, under my primary DVB-S2 I have the SD versions of Channel 4 unticked in the services tab.
(So the theory is, primary adapter will provide HD and is preferred, so my xbmc client will get HD preferred over SD)

So yesterday I had the following:

BBC2 (sd) being recorded
Channel4 (hd) being watched
Channel4 being recorded

Then a further recording was scheduled to start on Channel4 after the currently recording program. Because of the TVH overlap for recordings this tried to start at 5 to the hour (as expected).
XBMC then kicked me out of watching Ch4 live. I tried to retune to it (expecting it to reconnect, as it on the same mux, or find a spare card), and it failed, simply sitting at the buffering message (Not a refusal or no available messages, simply buffering).

Tried this several times, even tried other channels (Both SD and HD) and none would play at all, they all went into buffering state.

Logging in TVH looked like:

Oct 01 20:56:10 [DEBUG]:Service: Subscription "192.168.55.15 [ xbmc2 | XBMC Media Center ]": Adding adapter "_dev_dvb_adapter1_Montage_DS3103_TS202210714000_H_satconf_1" for service "Montage DS3103/TS2022/ASTRA: 10,714,000 kHz Horizontal (Default
(Port 0, Universal LNB))/Channel 4" 
Oct 01 20:56:10 [DEBUG]:Service: Subscription "192.168.55.15 [ xbmc2 | XBMC Media Center ]": Adding adapter "_dev_dvb_adapter1_Montage_DS3103_TS202210714000_H_satconf_1" for service "Montage DS3103/TS2022/ASTRA: 10,714,000 kHz Horizontal (Default
(Port 0, Universal LNB))/Channel 4" 
Oct 01 20:56:10 [DEBUG]:Service: Subscription "192.168.55.15 [ xbmc2 | XBMC Media Center ]": Adding adapter "_dev_dvb_adapter1_Montage_DS3103_TS202210714000_H_satconf_1" for service "Montage DS3103/TS2022/ASTRA: 10,714,000 kHz Horizontal (Default
(Port 0, Universal LNB))/Channel 4" 
Oct 01 20:56:10 [DEBUG]:Service: Subscription "192.168.55.15 [ xbmc2 | XBMC Media Center ]": Adding adapter "_dev_dvb_adapter1_Montage_DS3103_TS202212480000_V_satconf_1" for service "Montage DS3103/TS2022/ASTRA: 12,480,000 kHz Vertical (Default
(Port 0, Universal LNB))/Channel 4" 
Oct 01 20:56:10 [DEBUG]:Service: Subscription "192.168.55.15 [ xbmc2 | XBMC Media Center ]": Adding adapter "_dev_dvb_adapter1_Montage_DS3103_TS202211126500_V_satconf_1" for service "Montage DS3103/TS2022/ASTRA: 11,126,500 kHz Vertical (Default
(Port 0, Universal LNB))/Channel 4 HD" 
Oct 01 20:56:10 [DEBUG]:Service: Subscription "192.168.55.15 [ xbmc2 | XBMC Media Center ]": Probing adapter "_dev_dvb_adapter10_Conexant_CX24116_CX2411811126500_V_satconf_1" without stealing for service "Conexant CX24116/CX24118/ASTRA: 11,126,500 kHz Vertical (Default (Port 0, Universal LNB))/Channel 4 HD" 
Oct 01 20:56:10 [INFO]:subscription: "192.168.55.15" subscribing on "Channel 4", weight: 150, adapter: "Conexant CX24116/CX24118", network: "ASTRA", mux: "ASTRA: 11,126,500 kHz Vertical (Default (Port 0, Universal LNB))", provider: "BSkyB", service: "Channel 4 HD", quality: 100

Is this something that is a potential bug, or is this down to a set of events I've created? I'm wondering now if signal quality had anything to do with this, as in if my signal quality from one satcard, or possibly by dvb-t card was too poor, would it have been ignored here? I'm confused why the Phillips DVB-T card wasn't attempted (Checking the MUX for Channel4, signal on DVB-T is full)

Any ideas?