Finally found it. I checked bot the message files in /var/log the other day and there was no reference to DVB but I booted tonight and it was there. It would appear that the DVB-T tuners are not detected at all in DE-OpenBlackHole 1.4

Jan 1 01:00:53 dm8000 user.info kernel: [4294702.397000] DVB: registering new adapter (BCM7400)
Jan 1 01:00:53 dm8000 user.warn kernel: [4294702.501000] autodetecting NIMs...
Jan 1 01:00:53 dm8000 user.warn kernel: [4294702.502000] ret: -145, feid: 00
Jan 1 01:00:53 dm8000 user.warn kernel: [4294702.502000] ret: -145, feid: 00
Jan 1 01:00:53 dm8000 user.warn kernel: [4294702.502000] Initializing adapter 0 (BCM4501 (internal)-DVB-S2)
Jan 1 01:00:53 dm8000 user.info kernel: [4294702.506000] bcm4501: found 4501, revision 2(c0)
Jan 1 01:00:53 dm8000 user.warn kernel: [4294702.506000] bcm_initAP
Jan 1 01:00:53 dm8000 user.warn kernel: [4294702.511000] BCM4501: upload & start firmware
Jan 1 01:00:53 dm8000 user.debug kernel: [4294703.866000] bcm4501: ap not running - start now
Jan 1 01:00:53 dm8000 user.warn kernel: [4294703.877000] 4501 uCode 0x65
Jan 1 01:00:53 dm8000 user.warn kernel: [4294703.881000] DVB: registering adapter 0 frontend 0 (bcm4501)...
Jan 1 01:00:53 dm8000 user.warn kernel: [4294703.882000] Initializing adapter 1 (BCM4501 (internal)-DVB-S2)
Jan 1 01:00:53 dm8000 user.warn kernel: [4294703.882000] DVB: registering adapter 0 frontend 0 (bcm4501)...
Jan 1 01:00:53 dm8000 user.warn kernel: [4294703.883000] CI removed...
Jan 1 01:00:53 dm8000 user.warn kernel: [4294703.884000] CI removed...
Jan 1 01:00:53 dm8000 user.warn kernel: [4294703.885000] CI removed...
Jan 1 01:00:53 dm8000 user.warn kernel: [4294703.886000] CI removed...
Jan 1 01:00:53 dm8000 user.warn kernel: [4294703.890000] 9348 ms: 18