Have you tried security oriented distro Operator.iso by ussysadmin.org? It is based on knoppix and debian. Also it is one of the best network testing and pen testers tool?
Grandstream GS-HT802 2 Port Analog Telephone Adapter VoIP Phone & Device, Black
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VoIP IP Phone SIP WAN FV6020 Fanvil Gigabit Office Support IAX IAX2
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Yealink SIP-T41P PoE Ultra Elegant VoIP Phone
$29.95
Cisco 8841 CP-8841-K9 VoIP Business IP Phone (Charcoal)
$49.00
Cisco CP-7945G VOIP Phone With Stand & Handset Business IP Phone 7945
$3.00
New Cisco 7945G IP VoIP Gigabit GIGE Telephone Phone CP-7945G -
$24.95
Cisco CP-8861-K9 5-Line VoIP Business Phone w/ Stand & Handset
$24.98
Cisco CP-8845-K9 5 Line IP Video Phone - Charcoal
$25.00
LOT OF 10 Cisco CP-7841-K9 VoIP 4-Line Business Phone w/ Stand Handset Cord
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Cisco VG202XM Analog Voice Gateway VoIP -- [NEW/FULL KIT]
$76.00