Home router DNS sending scrambled IPs

Question

My network is behind a Technicolor TG582n provided by my ISP, it seems as if the firmware was modded to change some branding stuff and hide some features, but nothing much apart from that, I think. The problem is that by checking the DNS entries (via telnet) I can see the following:

{ISP}=> dns server host list
Address                                         Type Hostname                     TTL (s)                          Creator
192.168.1.103                                 * A    android-563cbc8707b8b48            0                      DHCP_Server
192.168.1.104                                 * A    android-724e830e4f3ce335           0                      DHCP_Server
192.168.1.107                                 * A    android-d01c6d882f6ab824           0                      DHCP_Server

However if I test some of the entries with nslookup I get this:

$ nslookup - 192.168.1.254
> android-563cbc8707b8b48
...
192.18.10.163

When it should be 192.168.1.103, as if the digits were scrambled somehow. It even fails with custom entries, I get:

> test
...
192.1.106.118

Instead of 192.168.1.1, so what could be the problem here? Is this feature broken on this brand and model or did my ISP really mess up the router's firmware?

Edit:

Also note that names like google.com work perfectly fine, i.e. for that name I am getting 216.58.193.46 as a response from the router and the address is correct.