I-O Selector Input 6 Channels doubts

[Mandragora]

Good morning
First of all, I would like to say that my knowledge of electronics is very limited.
I would like to do my own project and I have been reading a lot about the subject and I have collected ideas from various sites
I will start with the line input selector. It is a relay selector with 6 inputs and two outputs, there is a delay circuit that I do not understand well how it works but I have copied it from another site.
Please help me before starting production in case there is any error or the design can be improved.
Thank you very much in advance
Text translated with Google

 

[eclipsevl]

What’s the purpose of q1, q2?
I do not see any sense in their presence/connections.

 

[Mandragora]

Hi Eclipsevi
Yes, that's what I don't understand
On the site I copied it from, it seems to be that it acts as a switch to activate the output relay in the delay or mute circuit.
It seems to me that this is the area where I need more help
In fact, it's about having a mute on the output
Regards

 

[Mandragora]

Maybe it's better to remove this whole part??

 

[eclipsevl]

well, this circuit serves no function now. Better remove it.

 

[Mandragora]

Thanks Eclipsevi
Is it better this way?

 

[Mandragora]

What I want is to avoid the "plops" noise when changing lines but I think that the diodes already do that.

 

[Hicoco]

this circuit is 3 seconds delay to avoid noise on startup and work very well

 

[Mandragora]

Hi Hicoco, thanks for replying
Are you referring to the one from the first post?

 

[Hicoco]

Yes

 

[Mandragora]

Thank you very much Hicoco
This is what I needed to know to start building
Can the circuit be improved in any way??
Regards