# Wp7610/wp7611 volte

**URL:** <https://forum.sierrawireless.com/t/wp7610-wp7611-volte/26712>\
**Category:** WP Series\
**Created:** [April 1, 2022, 12:42pm UTC](https://forum.sierrawireless.com/t/wp7610-wp7611-volte/26712 "2022-04-01T12:42:01Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![kimk](https://avatars.discourse-cdn.com/v4/letter/k/bb73d2/32.png) [@kimk](https://forum.sierrawireless.com/u/kimk)\
**Post date:** [April 1, 2022, 12:42pm UTC](https://forum.sierrawireless.com/t/wp7610-wp7611-volte/26712/1 "2022-04-01T12:42:01Z")

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Hi All. I’m trying to make VOLTE calls on my device using AT commands, and I only get errors. We have devices in the field that stopped making calls when ATT shut down 3G. I can make calls with my device in Canada if KSRAT = 0. If I force it to LTE only KSRAT=5, I get errors. Any ideas how to make voice calls work for LTE.

SWI9X07Y\_02.37.03.00 73df45 jenkins 2020/04/08 10:59:14  
!GETRAT: LTE  
Index, Name, GW Band Mask L Band Mask 1 TDS Band Mask L Band Mask 2f  
00, All bands, 0000000006800000 000000000300381A 0000000000000000 0000000000000042  
!GETBAND: LTE B2  
!SELRAT: 06, LTE Only  
LTE Rx chan: 1075  
LTE Tx chan: 19075  
LTE CA state: INACTIVE  
EMM state: Registered Normal Service  
RRC state: RRC Connected  
PCC RxM RSSI: -83  
RSRP (dBm):-106  
PCC RxD RSSI: -95.  
RSRP (dBm): -135  
Tx Power: –  
TAC: 5A05 (23045)  
RSRQ (dB): -7  
Cell ID: 010B6117 (17522967)  
SINR (dB): 19.6  
IMS reg state: UNKNOWN  
IMS mode: Not Support  
IMS Srv State: UNKNOWN SMS,UNKNOWN VoIP  
LTE band: B2  
LTE bw: 15 MHz  
+CSQ: 17,99  
+CME ERROR: no network service

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**Author:** ![Donald](https://avatars.discourse-cdn.com/v4/letter/d/ac8455/32.png) [@Donald](https://forum.sierrawireless.com/u/Donald)\
**Post date:** [April 5, 2022, 4:41am UTC](https://forum.sierrawireless.com/t/wp7610-wp7611-volte/26712/2 "2022-04-05T04:41:54Z")

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Hi kimk,

As your log file provided, the _IMS Srv State: UNKNOWN SMS,UNKNOWN VoIP_ means your module does not have the VoLTE call feature.  
Please try configuring CID=2 with IMS APN for VoLTE certified with AT&T carrier that UE will connect to IMS client. Then use AT!GSTATUS? command to check IMS Srv State.

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**Author:** ![kimk](https://avatars.discourse-cdn.com/v4/letter/k/bb73d2/32.png) [@kimk](https://forum.sierrawireless.com/u/kimk)\
**Post date:** [April 5, 2022, 2:20pm UTC](https://forum.sierrawireless.com/t/wp7610-wp7611-volte/26712/3 "2022-04-05T14:20:44Z")

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Update I was finally able to make a VoLTE call by cheating and sticking my SIM in an iphone first. That tricked the network into providing the IMS service.  
It persisted for about 10 mins until the network realised it wasn’t an iphone and IMS went back to no service. It seems telecoms are determining IMS service based on IMEI allocations.