Alsamixer via ssh // Error opening terminal: xterm-256color

Hello,
with the following system:
piCorePlayer | piCorePlayer v6.1.0 | www v0009 | linux 4.19.122-pcpCore_v7 | piCore v10.3pCP | Squeezelite v1.9.6-1206-pCP
and a USB DAC,
squeezelite GUI sys:
Notes for your DAC.
Sorry, you cannot control a USB DAC from this page.
Login via ssh.
Use 'alsamixer' to change the ALSA output level.
Save mixer settings by using Save button below.

But when trying to open the alsamixer, the follwoing message comes in Linux Mint 18.3 Terminal:
Error opening terminal: xterm-256color.

How to solve this?