Why no soud in Sonic Frontiers Line 2 SE preamp


I have Sonic Frontiers Line 2 SE preamp. Every function is working, but no output sound. Badly need advice for direction. Tubes are fine, Mute function works fine, Standby function works. I do not use remote control. When I turn on the line 2, there two red lights on main board. I contacted Part Connection and thy suggested new matched tube set. I borrowed new set and it still did not make output sound. Please help me.
thyssen
JEA48,Yes, when I increased sound leel to my normal listening level, sound from speaker are extremely distorted. Unfortunately, I do not have the remote control. Do you think my preamp was limited output level by remote controller? Is there any method that I can check optical reader. Thanks!
I found this on diyaudio.com

The problem is that I have no output signal.By investigating with the schematic I found that the problem is related to the digital volume control which is made with two CS3310. If I short CS3310 input (pin 9 for instance) and output (pin 11) I obtain output signal (on left channel) at full volume. I did the same with pins 16 and 14 I obtain output signal on right channel at full vol....