Tvheadend

I have a central installation with version 4.3-210~g7644886-dirty (on a QNAP NAS) that acts as a SAT>IP client which connects to multiple TVH SAT>IP servers.
Up to version 4.3-295~ga9dffb7 on the servers all worked fine.
Today I tested version 4.3-322~g0960791 on the TVH SAT>IP servers and was unable to record on the central client (4.3-210~g7644886-dirty):

2017-08-10 10:55:57.287 dvr: entry 670e6af3ad0215377bc4eb4104f74091 "..." on "..." starting at 2017-08-10 10:26:30, scheduled for recording by "192.168.1...." 
2017-08-10 10:55:57.287 dvr: "..." on "..." recorder starting
2017-08-10 10:55:57.287 mpegts: ... in DVB-S Hotbird 13E - tuning on SAT>IP DVB-S Tuner #1 (192.168.1.xxx:9983)
2017-08-10 10:55:57.287 subscription: 05E3: "DVR: ..." subscribing on channel "...", weight: 100, adapter: "SAT>IP DVB-S Tuner #1 (192.168.1.xxx:9983)", network: "DVB-S Hotbird 13E", mux: "...", provider: "...", service: "...", profile="pass" 
2017-08-10 10:56:07.287 subscription: 05E3: service instance is bad, reason: No input detected
2017-08-10 10:56:07.287 mpegts: ... in DVB-S Hotbird 13E - tuning on SAT>IP DVB-S Tuner #1 (192.168.1.xxy:9983)
2017-08-10 10:56:07.287 subscription: 05E3: "DVR: ..." subscribing on channel "...", weight: 100, adapter: "SAT>IP DVB-S Tuner #1 (192.168.1.xxy:9983)", network: "DVB-S Hotbird 13E", mux: "...", provider: "...", service: "...", profile="pass" 
2017-08-10 10:56:17.287 subscription: 05E3: service instance is bad, reason: No input detected
2017-08-10 10:56:19.287 subscription: 05E3: No input source available for subscription "DVR: The Good Wife" to channel "..." 
2017-08-10 10:56:19.288 dvr: Recording unable to start: "...": No input detected

If I revert to version 4.3-295~ga9dffb7 all is working fine again.

What am I missing?