[A17]

I'm on VM broadband using the SuperHub 3.
From what I've read online the downstream power levels should be close to 0dbmv and if I remove an 8db forward path attenuator I can get much closer to it. I have been using it without the attenuator recently but the connection will randomly disconnect for a few hours unless I manually power cycle the hub, and there seems to be quite a lot of t3 timeout errors on the hub.
Here are the stats WITH the attenuator fitted:

Downstream bonded channels
Channel
Frequency(Hz)
Power(dBmV)
SNR(dB)
Modulation
Channel ID
1
299000000
-8.2
38.6
256 qam
55
2
323000000
-8.7
37.6
256 qam
58
3
315000000
-8.9
38.6
256 qam
57
4
307000000
-8.7
38.6
256 qam
56
5
291000000
-7.9
38.6
256 qam
54
6
283000000
-7.4
38.6
256 qam
53
7
275000000
-7
38.9
256 qam
52
8
267000000
-6.7
38.9
256 qam
51

Upstream bonded channels
Channel ID
Frequency(Hz)
Mode
Power(dBmV)
Modulation
Channel Bandwidth(Hz)
Symbol Rate (ksps)
2
39400000
ATDMA
44.8
16 qam
6400000
5120
4
25800000
ATDMA
44.8
16 qam
6400000
5120
3
32600000
ATDMA
44.8
16 qam
6400000
5120
1
46200000
ATDMA
44.8
16 qam
6400000
5120

Also, without the attenuator fitted I noticed that my downstream power levels randomly spike from around 0 to +7 at night and will be back to around 0 by the morning. Is this normal?
These T3 errors also showed on my old SH1 but the connection would only be lost when the DHCP expired.

All help is appreciated.