Not sure how long that line has been up when you took those stats, but there are quite a lot of HEC errors and Errored seconds, which indicates that there is a possible slight problem on that line at times.
This could be due to "normal SNRM" dipping in the evenings... but this could/will be why your connection seems sluggish and unresponsive at times.
That said.. I am not too worried about that just at present, because your line has just reset and the DLM will still be monitoring and its early days.
You still appear to be on the default SNR Margin of 6dB and its not yet turned on interleaving. Interleaving is normally one of the first steps that the DLM will activate to try and stabilise a line, I would not be too surprised if interleaving is switched on over the next few days if the HEC errors + ES + UAS continue.
The info gives us a little bit of a picture of what is happening on your line.. I must re-iterate at present Im not too concerned because your line may be one of those that perhaps needs a slightly higher SNRM to cope with normal day to day variations. When you get things like SES's and UAS's then you are likely to see 'pauses' when you are doing things like browsing. Theres a full explanation of what they mean here:-
line stat errors. The DLM will at some point adjust accordingly to try and compensate.
If I were you though, I would be using something like
routerstats to monitor the SNR on your line. This graphs your SNRM over periods of times and provides a good snapshot of your line. Its an invaluable tool for self diagnostic of adsl issues... and helps show what the DLM will be seeing.
Welcome to the wonderful world of adsl... and just how geeky it can get!
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btw.. the above is not related to you not appearing to be able to get over 8Mbps. The indications are there, that at least some of the time you should be able to get throughput speeds of around 14Mbps.