slowdown at BNG?

[#1]

I'm a new customer, and my line speeds seem fine, but I'm getting a lot of latency, and it appears to be at/beyond my cabinet:
the best case pings look great (12ms or so), but I often get hit with 500-1200ms!  
this really makes working from home difficult.
any chance this could be looked into?
some example MTRs:
[tt]
Start: Sun Jul  5 11:42:52 2015
HOST: smcghee-macbookair2.xxxxxxxxx      Loss%   Snt   Last   Avg  Best  Wrst StDev
 1.|-- dsldevice.lan                             0.0%    10    2.8   6.0   2.3  29.5   8.3
 2.|-- lo0.11.central11.pcl-bng02.plus.net       0.0%    10   16.1 241.5  11.9 712.8 284.1
 3.|-- irb.11.pcl-cr02.plus.net                  0.0%    10   12.2 235.7  12.0 711.8 266.6
 4.|-- ae1.ptw-cr02.plus.net                     0.0%    10   13.9 190.3  12.9 644.2 252.5
 5.|-- ae2.ptw-cr01.plus.net                     0.0%    10  230.0 172.7  11.8 585.2 222.8
 6.|-- 72.14.222.97                              0.0%    10  120.8 209.9  13.6 675.9 243.7
 7.|-- 209.85.246.242                            0.0%    10   63.3 174.8  13.1 622.8 219.2
 8.|-- 216.239.51.233                            0.0%    10   74.4 143.2  14.0 535.2 183.9
 9.|-- lhr14s27-in-f78.1e100.net                 0.0%     9   31.7  98.9  11.7 508.0 167.4
...
 1.|-- dsldevice.lan                             0.0%    10    3.0   4.8   2.1  20.8   5.6
 2.|-- lo0.11.central11.pcl-bng02.plus.net       0.0%    10   12.1 139.1  12.1 629.5 212.1
 3.|-- irb.11.pcl-cr02.plus.net                  0.0%    10  756.0 225.4  11.8 756.0 264.1
 4.|-- ae1.ptw-cr02.plus.net                    10.0%    10   58.0 142.7  12.5 489.9 162.9
 5.|-- ae2.ptw-cr01.plus.net                    10.0%    10  263.1 147.4  12.5 490.9 155.9
 6.|-- 72.14.222.97                             10.0%    10  209.8 126.3  13.2 474.0 145.8
 7.|-- 209.85.246.242                           10.0%    10  135.4  97.3  12.0 438.9 136.4
 8.|-- 216.239.51.233                           10.0%    10   55.7  83.0  11.8 477.0 149.4
 9.|-- lhr14s27-in-f78.1e100.net                10.0%    10   15.3  77.1  12.0 482.8 153.7[/tt]

[#2]

I believe this is bufferbloat.  If I upload anything, the latency gets terrible.
also:
http://www.dslreports.com/speedtest/801898
related, I currently have an Airport Extreme attached to the Sagemcom F@ST2704N modem/router.
I would prefer to have just a single router, but the sagemcom doesn't seem to be able to be put into modem-only mode 😕

[#3]

If you have a "previous ISP modem/router", use that in bridge mode instead.
Phil

[#4]

an update, I'm now using PPPoE/PPPoA via a DrayTek modem in bridged mode, so that should reduce the confusion of having two routers in a row.
That said, I still see bufferbloat on uploads:

HOST: smcghee-macbookpro2.roam.co Loss%   Snt   Last   Avg  Best  Wrst StDev
  1.|-- 10.0.1.1                   0.0%    10   16.7   3.6   1.1  16.7   4.7
  2.|-- lo0.11.central11.ptn-bng0  0.0%    10   12.9  13.0  10.0  23.5   3.9
  3.|-- irb.11.ptw-cr01.plus.net   0.0%    10   11.9  11.3  10.3  13.4   0.7
  4.|-- 72.14.222.97               0.0%    10   11.2  12.4   9.8  16.0   2.1
  5.|-- 209.85.246.244             0.0%    10   20.2  13.6  10.3  20.2   3.6
  6.|-- 209.85.250.171             0.0%    10   10.8  13.5  10.5  24.7   4.5
  7.|-- lhr08s05-in-f14.1e100.net  0.0%    10   11.0  12.0  10.1  13.8   1.1
smcghee-macbookpro2:~ smcghee$ mtr -tr google.com
Start: Thu Jul 16 14:59:11 2015
HOST: smcghee-macbookpro2.roam.co Loss%   Snt   Last   Avg  Best  Wrst StDev
  1.|-- 10.0.1.1                   0.0%    10    1.3   3.5   1.1  13.8   3.8
  2.|-- lo0.11.central11.ptn-bng0  0.0%    10  480.1 289.8  19.0 578.6 188.1
  3.|-- irb.11.ptw-cr01.plus.net   0.0%    10  500.8 280.1  11.1 556.8 184.0
  4.|-- 72.14.222.97               0.0%    10  531.5 269.6  23.8 531.5 175.1
  5.|-- 209.85.246.244            10.0%    10  298.3 237.1  10.7 494.8 175.3
  6.|-- 209.85.250.171            10.0%    10  293.1 240.1  14.0 479.6 167.6
  7.|-- lhr08s05-in-f14.1e100.net 10.0%    10  409.8 261.7  11.3 493.5 171.5

[#5]

i forgot to add:
http://www.dslreports.com/speedtest/870757
Bufferbloat: D  (where F is the worst)
<a href="http://www.dslreports.com/speedtest/870757">
<img src="http://www.dslreports.com/speedtest/870757.png"></a>

[#6]

bufferbloat on uploads will happen without QoS at your end.