Error on setting wifi connection off in multithreaded testing

Hello. I’m trying to run a multithreaded test using Appium with Selenium Grid, but after driver().setConnection(Connection.NONE) method is called, appium node crashes with this error:

Android bootstrap socket crashed: Error: read ECONNRESET
at Socket. (…/…/lib/bootstrap.js:87:21)
at emitOne (events.js:96:13)
at Socket.emit (events.js:188:7)
at emitErrorNT (net.js:1277:8)
at _combinedTickCallback (internal/process/next_tick.js:80:11)
at process._tickCallback (internal/process/next_tick.js:104:9)

It works perfectly fine with singlethreaded testing. Could you help me?

Appium version: 1.6.5
Selenium Grid version: 3.5.3
Appium java-client version: 5.0.0-BETA9