Your Guard is failing an extremely large amounts of circuits.

Hello, Its been several weeks, I am experiencing some problems with tor. Few weeks ago I started experiencing some connection drops, highly inconsistent bandwidth. I use to connect my RDP's through tor but connections are dropping abruptly after every few minutes, speed is also highly fluctuating, I never had this problem before. Then I decided to look at ARM, and I been seeing these messages over and over again.

TIME [WARN] Your Guard ---- ($****) is failing an extremely large amounts of circuits. This could indicate a route manipulation attack, extreme network overload or a bug. Success counts are ---. Use counts are ---. --- cicuits completed. --- were unusable, --- collapsed and --- timed out. For referrence, your timeout cutoff is 60 seconds.

TIME [WARN] Your Guard ----- ($****) is failing a very large amounts of circuits. Most likely this means The Tor network is overloaded, but it could also mean an attack against you or potentially the guard itself. Success counts .... etc.

And

circuit_package_rely_cell(): Bug: outgoing reply cell sent from ../src/or/rely.c:701 has n_chan==NULL. Dropping.

What is this? is this some kind of attack? I tried researching about same errors, but with no avail. I am using physical isolation technique through virtual environment. I was using Tor 0.2.8.9 then I decided to try older versions but still the same problem.

Trac:
Username: bug_bunny