SNR bouncing about all over the place

[#1]

I've had problems over the last few weeks and these have now settled down however I've noticed that my SNR bounces up and down without resyncs or anything.
I looked at it an hour ago and it was 10db now its showing 9.5. When the last resync (which I forced) happened a couple of days ago it was 8.0db. Is this normal?

[#2]

It's normal. The SNRM is dynamic as the noise levels are changing all the time. The target SNRM of 6dB, 9dB, 12dB etc is used when the modem sync with the exchange after that it will be changing as it's a real time measurement throughout the day. With it being lowest at night and higher in the day time.

[#3]

OK then how do I work out which target snrm I'm on as it goes below 9db sometimes and then at other times it's above so does it take it doesn't work tightly within bands.  

[#4]

You can only determine your SNRM target when you sync with the exchange. My modem stores this so it easy for me to see and mine was 11.9dB at the last resync, so a 12dB target. Currently it's at 12.9dB but at night this will drop to approximately 8dB.

[#5]

OK I can't see this information in the standard Thomson tg585 v7 router stats.
Link Information

Uptime: 1 day, 12:59:21
DSL Type: G.992.1 annex A
Bandwidth (Up/Down) [kbps/kbps]: 448 / 1,248
Data Transferred (Sent/Received) [kB/kB]: 0.00 / 0.00
Output Power (Up/Down) [dBm]: 12.0 / 16.0
Line Attenuation (Up/Down) [dB]: 31.5 / 63.5
SN Margin (Up/Down) [dB]: 13.0 / 10.0
Vendor ID (Local/Remote): TMMB / TSTC
Loss of Framing (Local/Remote): 0 / 0
Loss of Signal (Local/Remote): 0 / 0
Loss of Power (Local/Remote): 0 / 0
Loss of Link (Remote): 0
Error Seconds (Local/Remote): 7 / 0
FEC Errors (Up/Down): 3 / 60,629
CRC Errors (Up/Down): 3 / 1,284
HEC Errors (Up/Down): 2 / 1,117
I used to sync at 1.6 to 1.5mbps however since the problems the above speed is the fastest it has been. I guess it is because my SNR must have been increased because of the instability.