opentrasit.net problem?

we are AS 16592 (168.243.224.0/20) and are having problem reaching
168.234.136.0/24

the problem is very erratic, sometime we can reach them sometimes not (for
a 10-30 seconds period). problem arise from an opentransit.net hop as seen
in the following trace:

  1 <1 ms <1 ms <1 ms 205.235.28.65
  2 <1 ms <1 ms <1 ms 205.235.28.34
  3 1 ms 1 ms 1 ms 205.235.28.45
  4 1 ms 1 ms 1 ms 168.243.227.165
  5 3 ms 3 ms 3 ms 168.243.227.135
  6 12 ms 6 ms 10 ms 200.12.61.193
  7 195 ms 150 ms 90 ms 200.30.154.29
  8 185 ms 186 ms 241 ms 200.30.154.41
  9 291 ms 200 ms 109 ms 144.223.244.5
10 56 ms 54 ms 42 ms 144.232.20.17
11 125 ms 85 ms 82 ms 193.251.252.25
12 * * * Request timed out.
13 * * * Request timed out.
14 * * 146 ms 168.234.181.6
15 347 ms ^C

hop 11 is So5-0-0.MIABB1.Miami.opentransit.net and hop 12 is
TelecomElSalvador-OsiGuat.GW.opentransit.net

is opentransit.net present on NANOG? please contact me off-list.