Hi,
I noticed a weird difference between chain0 and chain1s performance.
I have 2 separate antennas (for each chain), and i tried testing each chain performance individually (by disabling and enabling each chain TX and RX), and for some reason, no matter which antenna i connect, chain1 always has poor performance compared to chain0.
So basically here are my test results (the difference is seen on speedtest.net results, as well on status tab where on chain1 signal parameters are way worse than on chain0):
19dbi dish - chain0: 10.3 / 2 Mbps
- chain1: 3.2 / 1.55 Mbps
17dbi panel antenna - chain0: 8.1 / 2 Mbps
- chain1: 3.0 / 1.6 Mbps

Could this be a broken chain1 chip/transmitter or is this normal? I tested this multiple times and the results were pretty much the same.

For anyone reading this - the problem was in outdated RouterOS.

After updating to current (now 1-2 months old) stable release, the problem went away, and both chains perform the same, independent of each other.