Hello, so it was working fine until a week or so ago. But no matter what I try I can't seem to get it to work.
Basically it's a P2P link(1KM) (having issues at the client side/station mode). When I connect to the AP, I get perfect 100% CCQ and TX/RX rates and I can ping the local/wan addresses just fine as you can see in the attachment. Here's what's mind boggling, the moment I actually browse something(even the local router page), ping fluctuates until timeout/RX rate drops to 1MB/s and browser cannot manage to load the pages. Nothing in LOG. Getting horrible speeds 0.4 MB/s on a 10MB/s link(sometimes upload speed goes up to 4MB/s but download is always around that 0.4 MB/s mark) . Throughput also starts to fluctuate on load as does CCQ from 70% to 90%. Signal is fine -69 to -72, SNR - 33 dB. I've tried switching to B/G, B only, G only, manual tx power settings, hw retries, distance, just about everything. Nothing seems to work. I even used another router to test, still messed up.
The router in question is a RB411(mipsbe) paired with a 24dbi antenna. I searched all over the forum. couldn't find a solution. That's about it, how do I get this sorted?

1km distance with a 24dbi antenna and -69 signal? That is low, would have expected something below -60.
The behavior is typical of interference scenario. How is the line of sight, any kind of obstruction? Even leafs of trees can cause problems.
Have you tried changing the frequency, change to superchannel?

AP(TP-link), actually it's less than 1 KM(probably about 100-300 metres). That should explain the signal strength. As I said earlier, I tried everything there is. It was working fine before, even if I connect to a Routerboard located roughly 3 KMS away, I get the same -67 to -75 signal strength but horrible performance like I'm experiencing with TP-link. For some reason RX rate keeps dropping to 1MB/s when I try to browse something. Line of sight is pretty clear. I set up another AP today just 20 metres away and it worked perfectly at ~-40dbi signal strength(same configuration but no CCQ and RX drops). Interference as in? What am I supposed to do now? In dire need of a solution. I can't seem to find one, I'm usually good at fixing these things.

AP in every test is TP-Link? If moving your AP 20m away gives you a hooping -40 in signal and better performance, it means there is either an alignment issue (i doubt it given your capabilities) or interference. Someone must have put something which greatly disturbs your signal path. I would recommend a 5GHz link if it is possible, or playing around with alignment, or some metal grids behind the antennas to see if they help isolating your signal path.

To make a PtP link like this you would be better off using a pair of SXTs, usually the SXT lite5

Nick

If there is 100% los

Try replacing your pigtails.

It could also be moisture in the connectors

And also try and re align both ends, you could be connecting to a side lobe

AP in every test is TP-Link? If moving your AP 20m away gives you a hooping -40 in signal and better performance, it means there is either an alignment issue (i doubt it given your capabilities) or interference. Someone must have put something which greatly disturbs your signal path. I would recommend a 5GHz link if it is possible, or playing around with alignment, or some metal grids behind the antennas to see if they help isolating your signal path.

No, as I said the manufacturer of the AP doesn't make a difference, be it a TP-Link or Mikrotik. And you misunderstood that AP part, I set up another AP(Client side alignment was the same, the one I'm having issues with.). It worked fine, but doesn't work properly when connecting to devices over long range. See, I can easily fix it by switching to a 5GHz link but I want to find a solution first. It isn't like it was messed up from the start, it was working for a good part of two years so you can see where I'm coming from. Especially since I've access to most of the routers/CPEs in the neighborhood. Noise floor isn't too bad either, varies from -102 to -105, frequency channels are properly set up as well/interference can't be an issue. If it was a hardware fault, I don't think it would've worked with the "TEST AP" I set up. Now?

If there is 100% los

Try replacing your pigtails.

It could also be moisture in the connectors

And also try and re align both ends, you could be connecting to a side lobe

Tried that already.

if your ap is a tplink maybe find a solution in the tplink forum. it is better to prefer the same manufacturer for long distance wireless bridges even of the same wireless chip because each manufacturer hardcodes some settings with different parameters and the most of them cannot be changed through administration menu. at this time of speaking i personaly know only mikrotik equipment capable of changing settings unchangeable in other routers/network equipment but of course has its limitations on hardware level instructions and needs advanced networking knowledge to setup.

if your ap is a tplink maybe find a solution in the tplink forum. it is better to prefer the same manufacturer for long distance wireless bridges even of the same wireless chip because each manufacturer hardcodes some settings with different parameters and the most of them cannot be changed through administration menu. at this time of speaking i personaly know only mikrotik equipment capable of changing settings unchangeable in other routers/network equipment but of course has its limitations on hardware level instructions and needs advanced networking knowledge to setup.

Did you even read the above posts?

Show us frequency usage and scan from this locations. Maybe it's to noisy and nothing will help you exept very good antennas.