Blynk server create an incorrect checksum with TCP communication

Hi!

I create a self running server with Pi2. My server run with Blynk 0.41.10 (and i already tested with v0.41.11) java8 ver.

I testing the network traffic, and found many errors. In Myserver->AndroidApp direction all packet use invalid checksum!

I use TcpDump for debug with the folowing parameters:
tcpdump -vvvXS | grep -v 192.168.50.15 | grep .19443

192.168.50.28.19443 > 254c50f7.nat.pool.telekom.hu.41438: Flags [P.], cksum 0x696d (incorrect -> 0xd77c), seq 1449282701:1449282764, ack 1848614674, win 243, options [nop,nop,TS val 475707204 ecr 5057440], length 63
254c50f7.nat.pool.telekom.hu.41438 > 192.168.50.28.19443: Flags [.], cksum 0x6e5c (correct), seq 1848614674, ack 1449282764, win 390, options [nop,nop,TS val 5057445 ecr 475707204], length 0
192.168.50.28.19443 > 254c50f7.nat.pool.telekom.hu.41438: Flags [P.], cksum 0x6966 (incorrect -> 0xf9fc), seq 1449282764:1449282820, ack 1848614674, win 243, options [nop,nop,TS val 475708066 ecr 5057445], length 56
254c50f7.nat.pool.telekom.hu.41438 > 192.168.50.28.19443: Flags [.], cksum 0x6a6e (correct), seq 1848614674, ack 1449282820, win 390, options [nop,nop,TS val 5057533 ecr 475708066], length 0
192.168.50.28.19443 > 254c50f7.nat.pool.telekom.hu.41438: Flags [P.], cksum 0x696d (incorrect -> 0x6c6e), seq 1449282820:1449282883, ack 1848614674, win 243, options [nop,nop,TS val 475708134 ecr 5057533], length 63
254c50f7.nat.pool.telekom.hu.41438 > 192.168.50.28.19443: Flags [.], cksum 0x69e6 (correct), seq 1848614674, ack 1449282883, win 390, options [nop,nop,TS val 5057538 ecr 475708134], length 0

How to repair the server checksum error?