I did not mention before, but there was quite a bit of static noise on the phone, sometimes louder, sometimes quieter. I finally removed the panel and tested the phone straight in the test socket - no noise at all, very clear line! Then I plugged back in the panel, plugged in the phone, and again, quiet line!
Now, regarding the broadband, the download speed in the past few days was quite high 54 - 58, but the upload very small. Yesterday I had about 2-3 Mbps. However, after removing and putting back the panel on the socket, it bumped to about 12 Mbps!! So the problem is within the master socket!
Did the pins cleared themselves while taking it out and putting back in? What do I have to do now? Would BT replace with a new one? How would I get back to the usual 16-17 Mbps upload speed?