Tvheadend

Hi guys,
i've installed tvheadend version 4.2.2, for the raspberry pi.
I'm able to scan the channels, but i'm not able to watch live tv.
If i try to open the Live player, on all the channels i receive an errore "An unknown error occurred"

2017-08-10 16:47:16.425 mpegts: 682MHz in italy - tuning on Realtek RTL2832 (DVB-T) : DVB-T #0
2017-08-10 16:47:16.427 subscription: 0088: "epggrab" unsubscribing
2017-08-10 16:47:16.437 subscription: 008B: "HTTP" subscribing on channel "RTL 102.5", weight: 150, adapter: "Realtek RTL2832 (DVB-T) : DVB-T #0", network: "italy", mux: "682MHz", provider: "Persidera", service: "RTL 102.5", profile="pass", hostname="192.168.178.155", username="osmc", client="Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/60.0.3112.90 Safari/537.36"
2017-08-10 16:47:21.425 mpegts: 682MHz in italy scan complete
2017-08-10 16:47:54.348 subscription: 008B: "HTTP" unsubscribing from "RTL 102.5", hostname="192.168.178.155", username="osmc", client="Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/60.0.3112.90 Safari/537.36"

here the debug logs, but I really don't know how to debug it.. Any clue?

Thanks so much