I'm having some weird connection problems with my home Wi-Fi network (ZyXEL adsl P-660HW-D1). I have a few devices connected to it, both by Ethernet wire and Wi-Fi, and only two of the devices have exhibited any symptoms (both of them owned and actively used by me). Any visiting device I've tried connecting to my home Wi-Fi has had no trouble. Both of the devices with problems work perfect in other Wi-Fi networks.
First there have been some connection problems with one (but only one!) of the computers connected to my network: Asus Eee PC 1001PX netbook (with Atheros AR2427 Wireless Network Adapter, running Xubuntu 9.10) 1) It has some random trouble connecting to the wlan (authentication failure), but when it gets a connection it stays connected without connection issues. 2) Sometimes ping results show some random packets with weirdly long latency, and occasional lost packet (<2% if even that).
Second, more serious is that my new Android device (GT-S5570 running 2.2.1) is having connection trouble. The device connects ok, gets an IP address, and sees all other computers on the network (using Overlook Fing). However, ping results are rather mixed. Depending on the attempt results come back with packet loss of anything from 100% to 0%, usually one or the other, but something around 20% or 60% happens quite often too. This happens trying to ping any of the devices on network, including the gateway (which, of course, is the problem). Other devices can ping each other just fine, independent of connection type (Wi-Fi or Ethernet wire).
The Android device always gets a connection, and stays connected to the Wi-Fi even when it's getting 100% packet loss.
The router has the original (which is also the latest) firmware, and I haven't meddled with the settings it came with - I woudn't know which settings to meddle with. Both devices have good signal strength. There are no conflicting Wi-Fi networks around.
How do I debug this further? What Wi-Fi settings could be causing this?
(Cross-posted to Android Enthusiasts since the main problem concerns the Android device.)