VoIP Phone w/Two VLANs - Unable to ping data network

Hello!
I have a peculiar problem. I have a few Yealink phones with the desktop plugged into them. I have the phone tag the PC port VLAN 1 and the WAN port on VLAN 154 (phone vlan).

192.168.254.1/24 (VLAN 1 - DATA)
192.168.154.1/24 (VLAN 154 - PHONES)

I have two main switches (routers) that have all ports VLAN 1 untagged (pvid: 1) and tagged all ports VLAN 154 (pvid: 1) - I believe this is correct. I don't do port based tagging, just vlan setup on the phones.

The phone connects to the PBX just fine, and the desktop PC can ping anything on the .254 network. However, if the phone is plugged into a standard (non-router) switch, and that switch connects to the main router. I cannot ping ANYTHING on that small 5-port switch in the .254 network.

For example, I have a printer connected to a small 5-port switch, along with the phone/PC pair, and I cannot ping that printer. But if I move the printer to the main switch, I can ping it just fine.

Why is this? Is it because the "dumb" switch isn't VLAN aware, or doesn't have Layer-3 features? Excuse my ignorance, I'm still new to vlans.

Thanks for any direction!