I have about 10 HP Procurve switches on my campus. My primary switch is a 5412zl and most of the others are either 5406zls and HP2920s. I've found that my phones don't connect to DHCP after firmware revision K_15_08_0013.swi for anything on the K software, but as soon as I downgrade to that revision or below, the phones connect instantly. As soon as a I upgrade past that revision, then they stop working (trying DHCP...). My new HP2920's don't work at all because their firmware is so new.
Here is the kicker though: If I put a dumb netgear switch in front of my HP switches with newer firmware and connect to the netgear with a power brick, then they'll get a DHCP address. I can then keep the power brick in and switch it to the wall port (or to a direct port on the switch) - but it won't reconnect if we lose power.
My phones use my default vlan for data and voip so they're simply untagged in the default vlan. I'm going to try putting in an option 43 tomorrow, but I don't see how that could help if the phones are in the same vlan as the dhcp server. Also, I can't set a static IP on the phones either.
If anyone has a suggestion, then I'd love to hear it. Thanks so much to anyone who might be able to help me out.