I have DP558 and WAP54G and this is similar configuration as you have it (DP500 and WET54G).
I needed quite sometime to enable it work, but after it is managed it works perfectly.
First thing what I learned is that MDIX need some time to check correct type of cable. WAP54G has UTP of type MDIX, which means that you don't need to worry if you should connect it to PC or other device such as Kiss player with straight or crossover cable. I don't know if WET54G has also this type of UTP, but I presume it has.
Second what I learned was, that even I connect Kiss via Linksys product to Linksys product, it is still needed to check configuration and not leave settings on default.
I left Kiss network setting on auto (DHCP) and I focused on connecting WAP54G to my router (which is WRT54G). When you get this thing to work you just plug Kiss in your WET and everything should work (or in some cases like described in other topics connect Kiss to WET via switch).
1. Setup WET54G with IP which is very close to your router IP and it is not in DHCP scope. Example:
- Router has IP 10.15.27.1 Mask 255.255.255.0
- DHCP in router is set to reserve numbers from 10.15.27.100 up to 10.15.27.199
- Set IP of WET54G to 10.15.27.2 same mask and of course gateway should be 10.15.27.1 (IP from router)
2. Wireless settings must be exactly same and it is good that you check extended settings also. So check:
- SSID must be same
- channel must be same. In my case it happened that router was set on channel 11 and WAP was set on channel 6
- if you have security, check that security settings are same (WEP key...)
- Mode must also be same. If I had router wireless mode set to Mixed and WAP set to G-Only it didn't work at least at my place. When I set both to mixed or both to G-Only it worked.
- Usually you don't need MAC cloning. In our place cable providers request this for connection, because they don't use password. I can't answer on this question maybe someone else can give you more detailed answer
- Check also advanced mode. RTS Threshold in my WAP54G was set to max 2346, while in router max was 2347. I think it shouldn't have impact if you leave default values, but I set it to same value 2346
- After you set all settings and save them restart your WET and check again settings. I have checked and saw that some values were not saved. I don't know why. Maybe I didn't press Save settings every time when I set something. So if I saw settings which I wanted after restart of my WAP then I know that things should work.
- I have disconnected my WAP from router's Ethernet and tried to connect to it via wireless, but without success. What was wrong? I don't know but then I just connect Kiss to WAP turn it on and it worked after 30 seconds. I don't know if WAP and WRT54G needed some time to connect between themselves or eventually client connected to WAP (Kiss player) requested something which forced connection? Anyway after that I am now able to connect to my WAP at any time.
If something of this will help, good, if not then good luck with searching next solution.