If you disconnect the LG TV from the power supply and then switch it on again, there is a small time window during the boot-up sequence where a TCP connection can be established. Approx. 7 seconds. If the LGTV2 client establishes the connection to the LG TV exactly during this time, the client hangs forever and blocks any further processes.

Do you have an idea or a workaround to prevent this?

You can test it by pinging the TV during boot-up. If the server responds, try to establish a connection with your LGTV2 client.
Important: Before disconnecting the LG TV from the power supply, switch off the TV with the remote control and wait 10 minutes until the pixel cleaning process has been completed. This process runs in the background after switching off the TV.

(Windows ping)
c:\>ping 192.168.1.70 -t

Pinging 192.168.1.70 with 32 bytes of data:
Reply from 192.168.1.10: Destination host unreachable. <--- Boot up LGTV
Reply from 192.168.1.10: Destination host unreachable.
Reply from 192.168.1.10: Destination host unreachable.
Reply from 192.168.1.10: Destination host unreachable.
Reply from 192.168.1.10: Destination host unreachable.
Reply from 192.168.1.10: Destination host unreachable.
Reply from 192.168.1.10: Destination host unreachable.
Reply from 192.168.1.70: bytes=32 time=5ms TTL=63 <--- Connect here
Reply from 192.168.1.70: bytes=32 time=4ms TTL=63
Reply from 192.168.1.70: bytes=32 time=5ms TTL=63
Reply from 192.168.1.70: bytes=32 time=5ms TTL=63
Reply from 192.168.1.70: bytes=32 time=5ms TTL=63
Reply from 192.168.1.70: bytes=32 time=5ms TTL=63
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Reply from 192.168.1.10: Destination host unreachable.
Reply from 192.168.1.10: Destination host unreachable.
Reply from 192.168.1.10: Destination host unreachable.