spikes...spikes everywhere!

[peatonplayz]

hey everyone

for the last few days I had some issues with my internet connection and I was able to find out the cause of the problems.

I'm using a mikrotik lite5 to connect to a ISP that provides point to point internet connection. for the last week I noticed  I was having ping spikes and after calling ISP for 50 times I realized there was a problem with my 

internal ping (from PC to the device on the roof) the problem occurs every few minutes but I have a good download and upload speed. 

using winbox I found out the CPU usage of the device also jumps up to 50% while even downloading or testing via speedtest.net CPU usage is around 30% max. 

does anyone know what may be cause the problem?

P.S: I removed any device in between and tested with the PoE connected straight to lan behind the PC/used a different PoE cable/ updated firmware/ reset and redone the configuration. nothing has changed so far.