virtualbox.org

I updated from 4.3.20 to 4.3.22 on Windows 7-64, then updated my Win7-64 client to GA 4.3.22. I noticed that Winamp would be playing a song from a network share and freeze on a particular spot and repeat the same note. I then checked the network, cpu, and memory. The only odd thing was that the network usage went down to zero at the same time as the playback faltered. So, I set up a ping to my home router/NAT device, and the playback failure coincided with a "general failure" of the pings (5 failed to be exact.) The Host was also pinging the same router at the same time, and did NOT experience this behavior.
So, on my guest, I uninstalled GA, rebooted, reinstalled GA 4.3.20, and STILL saw the issue. Reverted the host back to 4.3.20, and the problem went away.
I'm just waiting for the next stable release, and not really interested in troubleshooting, but wanted to post what I saw in case someone else sees something similar. Could just be me.

You are not alone.

I had awful network issues using 4.3.22, on both host and guests.
Connection timeouts in mail, web browsing, etc.
Some web sites that load as you scroll would just freeze.

I went back to 4.3.20 (host, extension pack, and guest additions).
Now the network works well again.

Host: openSUSE 13.2, 64 bit - 8 GiB RAM, 4 cpus (not threads), 1 TB free disk space (SATA).
Guest 1: Win 7 Pro 64 bit - 2 Gib ram, 1 cpu, 80 GB dynamic disk (50 GB free) on virtual SATA
Guest 2: openSUSE 13.2, 64 bit - 2GB ram, 1 cpu, 80 GB dynamic disk (60GB free) on virtual SATA
VT-X enabled on host and guests.

You are so "not alone" that creating a new topic to discuss your case seems quite redundant.

See Discuss the 4.3.22 release.