What version of firmware is most reliable for this device?

With the same configuration:

5.26 - RB works stablly, but the traffic of some devices stablly drops.

6.11 - All devices works, but communication often interrupts.

both of these versions should work reliablly, v5.26 and v6.11

what do you mean by "drops"? you should clarfiy the issue in more detail, the problem could be somewhere else.

Ok. I've described this problem shortly in "Routerboard Hardware".
I'll describe it in more detail here.
Sorry, but there will be a lot of words.

We have two offices, connected with IPSEC VPN tunnel over Internet.
Before the tunnel was formed by two Cisco PIX.
There is a Panasonic PBX in office A and 2 Panasonic IP phones (KX-NT265RU and KX-NT321RU) in office B.
They use MGCP and RTP protocols. Nobody knows what is the difference between protocols of these models.
I use sniffer for comparing them and find no difference.

Office B is connected to Internet with ADSL modem.

We replaced Cisco PIX in office B with RB951 with firmware 5.26. All works, tunnel works, KX-NT321 works, but KX-NT265 do not transfer voice to PBX.
Sniffer shows normal flow of packets between phone and RB, but no sound (((
In the opposite direction the sound is normal.

I replaced RB with the same device (firmware 6.11) and the same configuration.
All works! Both phones works!
But the connection is frequently interrupted, both the tunnel and access to the Internet.
For a some time the connection is stable, but then again begin interruptions.

Phone KX-NT265 is not damaged.

v6.11 with 56 wireless clients (phones) connected and speedtest show 30mbps on the phone...

v6.11 with 56 wireless clients (phones) connected and speedtest show 30mbps on the phone...

And what it means?

it means the device works perfectly with 6.11 doh...

it means the device works perfectly with 6.11 doh...

It means the device works perfectly in some cases.
It does not mean the device works perfectly in all cases.

Sometimes the last version is not the most stable version. It was a sense of my question.

But ver 6.11 is not acceptable for me. (((

It is nearly impossible to replicate such setup here, maybe you need to contact support of the phone manufacturer? It seems the other models work fine, just one of them doesn't.

It is nearly impossible to replicate such setup here, maybe you need to contact support of the phone manufacturer? It seems the other models work fine, just one of them doesn't.

Certainly, I asked about it at Panasonic forums and several Panasonic dealers. Nobody knows.
It is clear that nobody will study a subtlety of interaction of the equipment of different firms.

Therefore I try to formulate here questions which experts Mikrotik can answer without consideration of Panasonic equipment.
On the other hand, differences in protocols of these models of phones was not detected whereas the difference in behavior of different versions of RouterOs is visible.

So, what I wanted to learn?
1. Somebody came up against this situation? As I understand, no. The question is closed.
2. Is there fw version more stable than 5.26 and 6.11? As I understand, no. The question is closed.
3. Whether the problem can be connected with that the ADSL channel, which, first, quite slow and, secondly, the asymmetric is used. We will notice that the sound doesn't pass in that direction in which the channel is weakest.

The third question obviously not for a begginers forum. I not really hope to receive here answer, but I plan to carry out a number of experiments. As a result, probably, we will either change the channel, or refuse from Mikrotik if other equipment shows the best results.

Obviously, I need to thank all for attention and to consider a subject closed.

I thank all for attention and I consider a subject closed.

I'm new to MikroTik so help me out here.

I have two RB950G-2HnD routers, both seem to be working fine on version 5.24.

Generally speaking should we always update within a general release? I mean should I upgrade to 5.26 just to keep current?

OR when a new release comes out and what I have is working, do I upgrade to 6.12?

Just looking for general guidance.

Thanks,

Bill in Gig Harbor, WA, USA