It's not DLM that's lowering your SNRM. If you look at the end of the line stats which you posted, the uptime was nearly 12 days. When DLM lowers the target SNRM, the connection drops and reconnects. Also, the connection speed will have remained the same over that nearly 12 days, so when you say that the speed dropped I presume you're referring to the download speed as measured using a speedtester? That will be due to some other cause.