So had an apt-get source operation fail several times and I assumed it was network wonkiness until I read the actual error:

Need to get 10.6 MB of source archives.
Get:1 http://ftp.us.debian.org/debian unstable/main subversion 1.9.7-2 (tar) [10.6 MB]
Err:1 http://ftp.us.debian.org/debian unstable/main subversion 1.9.7-2 (tar)
File has unexpected size (1750 != 10643686). Mirror sync in progress?
Hashes of expected file:
- SHA256:c72a209c883e20245f14c4e644803f50ae83ae24652e385ff5e82300a0d06c3c
- Filesize:10643686 [weak]
- MD5Sum:97938ca331b33291c5771a514f37a3dc [weak]
E: Failed to fetch http://192.168.1.1/virus/blockpage?n...f55d2e27&tid=5 File has unexpected size (1750 != 10643686). Mirror sync in progress?
Hashes of expected file:
- SHA256:c72a209c883e20245f14c4e644803f50ae83ae24652e385ff5e82300a0d06c3c
- Filesize:10643686 [weak]
- MD5Sum:97938ca331b33291c5771a514f37a3dc [weak]
E: Failed to fetch some archives.


You'll notice the url is not exactly a debian mirror url: untanglefail.png