Please be informed that our FE already checked this problem with customer end (Mr. Rangsan +668 9904 7122). They have check the SNR value at outside plant is narmal gain. After that they have check at SDF connector in customer building and found SNR margin lower than gain. So, they have re-joint connector at SDF. Unfortunately , the SNR value still low. So, the problem is in internal wire at customer building.
Our FE alarady informed Mr. Rangsan +668 9904 7122 for this issue. He would like to keep monitoring if the problem still occurs. He will co-operation with their technician building and our FE to fixed this issue.