I experienced the "dropping out" problem for the first time ever last night, but not with drums.  Instead, using Trilian random bass notes would not play.  I did a freeze the file seems to be fine BUT when I did that then the drums started dropping out randomly.  No drum map involved.  Very odd.

You probably just need to increase your Prepare Using Buffer for MIDI to 500 per post #2.

Hi there!
The same disaster with X3 + Addictive Drums 2
Deleting the .ini and rising up the MIDI buffer doesn't make any sense...
Do I understand correctly that the only one solution is to disable the drum map?
Will the drums still play notes after map will be disabled? In such way how it's done?
Thanks!

Deleting the .ini and rising up the MIDI buffer doesn't make any sense...

If it solves your problem then it makes perfect sense.

Do I understand correctly that the only one solution is to disable the drum map?

Not necessarily. What exactly is your problem, what have you done so far to try and resolve it and please list your full computer spec, including interface & driver mode.

Will the drums still play notes after map will be disabled?

Yes. The drum map just overlays the piano roll, remove the map and the notes will still be there.

Not necessarily. What exactly is your problem, what have you done so far to try and resolve it and please list your full computer spec, including interface & driver mode.

The problem is that today suddenly the AD2 started to mute some notes. In other words randomly some drums doesn't sound during playback.
I've try to rise the midi buffer from 250 to 2500, deleted the .ini. Changed the audio interface (RME 9632) buffer to  256; 512; 1024
My PC is
i5 2500K
8GB RAM
Windows 7x64
HDD (not SSD)
Driver mode - can't answer exactly cause the RME does it in it's way (I guess).
Could you please describe how to remove the drum map?

To eliminate the drum map, you can assign the output of the MIDI track directly to AD2. This will bypass the map, but leave it in the project. To remove the map from the project altogether, choose 'Drum Map Manager' from the MIDI track output, and delete the map.
 
But if you actually bumped the MIDI Prepare Using buffer all the way to 2500 from 250, try 500 as recommended earlier; too high can also be problematic.
 
Did you compose the MIDI for this drum track yourself, or is it from a 3rd party? Are all the parts in a single clip? Is it hard-quantized? What's the project tempo? Sometimes changing the tempo or moving hard-quantized notes a tick or two off the grid will eliminate problems with dropped notes that don't respond to increasing the Prepare Using buffer.

Ok, I will try to bypass the drum map.
The first part was composed by me, the second - partly - few notes from 'beats' and then modified.
Notes were quantized by 1/16 without additional options. The tempo is 200.
But I observed that just opening the AD2 and playing any beat will cause the same problem from that project.
 
Opening another project doesn't rise such issues :(
 
P.S. Just bypassed the drum map - no success

full image -

It seems that my problem was caused by the third-party plugin placed on master bus.
Could say - SOLVED :D

01
Ok, I will try to bypass the drum map.
The first part was composed by me, the second - partly - few notes from 'beats' and then modified.
Notes were quantized by 1/16 without additional options. The tempo is 200.
But I observed that just opening the AD2 and playing any beat will cause the same problem from that project.
 
Opening another project doesn't rise such issues :(
 
P.S. Just bypassed the drum map - no success

full image -

Just one point. If that image in the prv is your drum track then you need to shorten all the notes to somewhere between 30 & 60 ticks.
 
Having drum notes extending that long can and will cause problems

Opps, sorry. In the piano roll it was the bass part. Does your advice applies also to it?