FXS Problem with R24FXX

I'm running TrixBox CE 2.6.2.2 and have a R24FXX card with 4 FXO and 1 FXS modules installed. I've run setup-rhino and then setup-pstn. I've tested the first FXO port and can send and receive calls to a trunk (Zap channel 1). However, I can't get a dialtone or place/receive a call on the analog phone I've plugged into the first FXS port (Zap channel 9). I do have power connected to the card and the LEDs all seem to be in a reasonable state. From looking at the SureTeq site and searching around it seems that I should probably at least get dialtone, but all I get is a background 60-cycle hum. I can hear hook signals and dialtones when I press keys on the phone. I'm guess I not sure how to proceed from here. Note that the zapata_additional.conf I've attached below is trying to set the extension of the analog phone to 6009 (matching the entry for channel 9 in zapata-auto.conf). I've tried other extension settings as well, since I'm not sure whether to match that setting or not, but I get the same (non-)result. Any ideas?

CONTENTS OF ZAPATA-AUTO.CONF:

; Autogenerated by /usr/sbin/genzaptelconf -- do not hand edit
; Zaptel Channels Configurations (zapata.conf)
;
; This is not intended to be a complete zapata.conf. Rather, it is intended
; to be #include-d by /etc/zapata.conf that will include the global settings
;

; Span 1: Rhino RCB24FXX/1 "Rhino RCB24FXX/1" (MASTER)
;;; line="1 FXO/1/0"
signalling=fxs_ks
callerid=asreceived
group=0
context=from-zaptel
channel => 1
context=default

;;; line="2 FXO/1/1"
signalling=fxs_ks
callerid=asreceived
group=0
context=from-zaptel
channel => 2
context=default

;;; line="3 FXO/1/2"
signalling=fxs_ks
callerid=asreceived
group=0
context=from-zaptel
channel => 3
context=default

;;; line="4 FXO/1/3"
signalling=fxs_ks
callerid=asreceived
group=0
context=from-zaptel
channel => 4
context=default

;;; line="5 FXO/1/4"
signalling=fxs_ks
callerid=asreceived
group=0
context=from-zaptel
channel => 5
context=default

;;; line="6 FXO/1/5"
signalling=fxs_ks
callerid=asreceived
group=0
context=from-zaptel
channel => 6
context=default

;;; line="7 FXO/1/6"
signalling=fxs_ks
callerid=asreceived
group=0
context=from-zaptel
channel => 7
context=default

;;; line="8 FXO/1/7"
signalling=fxs_ks
callerid=asreceived
group=0
context=from-zaptel
channel => 8
context=default

;;; line="9 FXS/1/8"
signalling=fxo_ks
callerid="Channel 9"
mailbox=6009
group=5
context=from-internal
channel => 9
callerid=
mailbox=
group=
context=default

;;; line="10 FXS/1/9"
signalling=fxo_ks
callerid="Channel 10"
mailbox=6010
group=5
context=from-internal
channel => 10
callerid=
mailbox=
group=
context=default

CONTENTS OF ZAPATA_ADDITIONAL.CONF:

;--------------------------------------------------------------------------------;
; Do NOT edit this file as it is auto-generated by trixbox. All modifications to ;
; this file must be done via the web gui. There are alternative files to make ;
; custom modifications. ;
;--------------------------------------------------------------------------------;
;

;;;;;;[6009]
signalling=fxo_ks
pickupgroup=
mailbox=6009@device
immediate=no
echotraining=800
echocancelwhenbridged=no
echocancel=yes
context=from-internal
callprogress=no
callgroup=
callerid=device
busydetect=no
busycount=7
accountcode=
channel=>9